Deprecate std::filesystem namespace include

Clang-tidy is complaining about our using fs = ... directives.  These
were originally added to handle boost::filesystem vs
std::experimental::filesystem vs std::filesystem between the various
compilers.  Now that we're all on std::filesystem, this redefinition can
be removed.

```
ChassisIntrusionSensor.hpp:11:11: error: namespace alias decl 'fs' is unused [misc-unused-alias-decls,-warnings-as-errors]
   11 | namespace fs = std::filesystem;
```

Tested: code compiles

Change-Id: If4b968ff9cceb4038f526321d3c7c11563ffbce9
Signed-off-by: Ed Tanous <etanous@nvidia.com>
diff --git a/src/intel-cpu/IntelCPUSensorMain.cpp b/src/intel-cpu/IntelCPUSensorMain.cpp
index 4ad0853..be88a0d 100644
--- a/src/intel-cpu/IntelCPUSensorMain.cpp
+++ b/src/intel-cpu/IntelCPUSensorMain.cpp
@@ -101,8 +101,6 @@
 static constexpr const char* rescanPath = "/sys/bus/peci/rescan";
 static constexpr const unsigned int rankNumMax = 8;
 
-namespace fs = std::filesystem;
-
 static constexpr auto sensorTypes{std::to_array<const char*>({"XeonCPU"})};
 static constexpr auto hiddenProps{std::to_array<const char*>(
     {IntelCPUSensor::labelTcontrol, "Tthrottle", "Tjmax"})};
@@ -192,8 +190,8 @@
         return false;
     }
 
-    std::vector<fs::path> hwmonNamePaths;
-    findFiles(fs::path(peciDevPath),
+    std::vector<std::filesystem::path> hwmonNamePaths;
+    findFiles(std::filesystem::path(peciDevPath),
               R"(peci-\d+/\d+-.+/peci[-_].+/hwmon/hwmon\d+/name$)",
               hwmonNamePaths, 6);
     if (hwmonNamePaths.empty())
@@ -205,7 +203,7 @@
     boost::container::flat_set<std::string> scannedDirectories;
     boost::container::flat_set<std::string> createdSensors;
 
-    for (const fs::path& hwmonNamePath : hwmonNamePaths)
+    for (const std::filesystem::path& hwmonNamePath : hwmonNamePaths)
     {
         auto hwmonDirectory = hwmonNamePath.parent_path();
 
@@ -215,7 +213,7 @@
             continue; // already searched this path
         }
 
-        fs::path::iterator it = hwmonNamePath.begin();
+        std::filesystem::path::iterator it = hwmonNamePath.begin();
         std::advance(it, 6); // pick the 6th part for a PECI client device name
         std::string deviceName = *it;
 
@@ -307,7 +305,7 @@
             std::visit(VariantToUnsignedIntVisitor(), findCpuId->second);
 
         auto directory = hwmonNamePath.parent_path();
-        std::vector<fs::path> inputPaths;
+        std::vector<std::filesystem::path> inputPaths;
         if (!findFiles(directory, R"((temp|power)\d+_(input|average|cap)$)",
                        inputPaths, 0))
         {
@@ -504,11 +502,11 @@
         std::fstream rescan{rescanPath, std::ios::out};
         if (rescan.is_open())
         {
-            std::vector<fs::path> peciPaths;
+            std::vector<std::filesystem::path> peciPaths;
             std::ostringstream searchPath;
             searchPath << std::hex << "peci-" << config.bus << "/" << config.bus
                        << "-" << config.addr;
-            findFiles(fs::path(peciDevPath + searchPath.str()),
+            findFiles(std::filesystem::path(peciDevPath + searchPath.str()),
                       R"(peci_cpu.dimmtemp.+/hwmon/hwmon\d+/name$)", peciPaths,
                       3);
             if (!peciPaths.empty())
@@ -518,7 +516,7 @@
             }
             else
             {
-                findFiles(fs::path(peciDevPath + searchPath.str()),
+                findFiles(std::filesystem::path(peciDevPath + searchPath.str()),
                           R"(peci_cpu.cputemp.+/hwmon/hwmon\d+/name$)",
                           peciPaths, 3);
                 if (!peciPaths.empty())