Remove findStringName/Handle functions

Use the `find` functions in BiosStringTable.

Tested: all the code changes are about building bios tables.
tested on fp5280g2, with json
https://gist.github.com/wangzqbj/b24558331cb35d14fca3b555ef03e458

saw the built tables are as expected.

$ pldmtool bios GetBIOSTable -t 0
...
...
PLDM StringTable:
BIOSStringHandle : BIOSString
0 : CodeUpdatePolicy
1 : Concurrent
2 : Disruptive
3 : Led
4 : Model
5 : OUTLET
6 : Off
7 : On
8 : str_example3

$ pldmtool bios GetBIOSTable -t 1
...
...
PLDM AttributeTable:
AttributeHandle: 0, AttributeNameHandle: 0(CodeUpdatePolicy)
	AttributeType: BIOSEnumerationReadOnly
	NumberOfPossibleValues: 2
		PossibleValueStringHandle[0] = 1(Concurrent)
		PossibleValueStringHandle[1] = 2(Disruptive)
	NumberOfDefaultValues: 1
		DefaultValueStringHandleIndex[0] = 0, StringHandle = 1(Concurrent)
AttributeHandle: 1, AttributeNameHandle: 3(Led)
	AttributeType: BIOSEnumeration
	NumberOfPossibleValues: 2
		PossibleValueStringHandle[0] = 7(On)
		PossibleValueStringHandle[1] = 6(Off)
	NumberOfDefaultValues: 1
		DefaultValueStringHandleIndex[0] = 1, StringHandle = 6(Off)
AttributeHandle: 2, AttributeNameHandle: 5(OUTLET)
	AttributeType: BIOSInteger
	LowerBound: 0
	UpperBound: 68002
	ScalarIncrement: 1
	DefaultValue: 0
AttributeHandle: 3, AttributeNameHandle: 4(Model)
	AttributeType: BIOSString
	StringType: 0x01
	MinimumStringLength: 1
	MaximumStringLength: 100
	DefaultStringLength: 8
	DefaultString: FP5280G2
AttributeHandle: 4, AttributeNameHandle: 8(str_example3)
	AttributeType: BIOSStringReadOnly
	StringType: 0x00
	MinimumStringLength: 1
	MaximumStringLength: 100
	DefaultStringLength: 2
	DefaultString: ef

$ pldmtool bios GetBIOSTable -t 2
...
...
PLDM AttributeValueTable:
AttributeHandle: 0
	AttributeType: BIOSEnumerationReadOnly
	NumberOfCurrentValues: 1
	CurrentValueStringHandleIndex[0] = 0, StringHandle = 1(Concurrent)
AttributeHandle: 1
	AttributeType: BIOSEnumeration
	NumberOfCurrentValues: 1
	CurrentValueStringHandleIndex[0] = 1, StringHandle = 6(Off)
AttributeHandle: 2
	AttributeType: BIOSInteger
	CurrentValue: 0
AttributeHandle: 3
	AttributeType: BIOSString
	CurrentStringLength: 12
	CurrentString: powersupply0
AttributeHandle: 4
	AttributeType: BIOSStringReadOnly
	CurrentStringLength: 2
	CurrentString: ef

Signed-off-by: John Wang <wangzqbj@inspur.com>
Change-Id: Iba775caffcdfa51d780cd9c211572d3a359b80b4
diff --git a/libpldmresponder/bios_table.hpp b/libpldmresponder/bios_table.hpp
index b99b7a6..67503df 100644
--- a/libpldmresponder/bios_table.hpp
+++ b/libpldmresponder/bios_table.hpp
@@ -71,22 +71,37 @@
     fs::path filePath;
 };
 
-class BIOSStringTable : public BIOSTable
+class BIOSStringTable
 {
   public:
-    /** @brief Ctor - set file path to persist BIOS String table
+    /** @brief Constructs BIOSStringTable
      *
-     *  @param[in] filePath - file where BIOS table should be persisted
+     *  @param[in] stringTable - The stringTable in RAM
      */
-    BIOSStringTable(const char* filePath);
+    BIOSStringTable(const Table& stringTable);
+
+    /** @brief Constructs BIOSStringTable
+     *
+     *  @param[in] biosTable - The BIOSTable
+     */
+    BIOSStringTable(const BIOSTable& biosTable);
 
     /** @brief Find the string name from the BIOS string table for a string
      * handle
      *  @param[in] handle - string handle
-     *  @return - std::string - name of the corresponding BIOS string
+     *  @return name of the corresponding BIOS string
+     *  @throw std::invalid_argument if the string can not be found.
      */
     std::string findString(uint16_t handle) const;
 
+    /** @brief Find the string handle from the BIOS string table by the given
+     *         name
+     *  @param[in] name - name of the BIOS string
+     *  @return handle of the string
+     *  @throw std::invalid_argument if the string can not be found
+     */
+    uint16_t findHandle(const std::string& name) const;
+
   private:
     Table stringTable;
 };