cleanup: Remove all warning errors for the Meson build support

Remove all the build warning to prepare for the meson build.
Meson build will be in
https://gerrit.openbmc-project.xyz/c/openbmc/phosphor-host-ipmid/+/47748

Tested:
Ipmi command works fine the cleanup.
```
$ systemctl status phosphor-ipmi-host
● phosphor-ipmi-host.service - Phosphor Inband IPMI
     Loaded: loaded (/lib/systemd/system/phosphor-ipmi-host.service; enabled; vendor preset: enabled)
     Active: active (running) since Thu 1970-01-08 21:20:56 UTC; 21s ago
   Main PID: 24987 (ipmid)
     CGroup: /system.slice/phosphor-ipmi-host.service
             └─24987 /tmp/ipmid

Jan 08 21:20:56 $HOST ipmid[24987]: Registering OEM:[0X002B79], Cmd:[0X30] for Ethstats Commands
Jan 08 21:20:56 $HOST ipmid[24987]: Registering OEM:[0X00C2CF], Cmd:[0X30] for Ethstats Commands
Jan 08 21:20:56 $HOST ipmid[24987]: Registering OEM:[0X002B79], Cmd:[0X32] for Sys Commands
Jan 08 21:20:56 $HOST ipmid[24987]: Registering OEM:[0X002B79], Cmd:[0X02] for I2C
Jan 08 21:20:56 $HOST ipmid[24987]: Registering OEM:[0X00C2CF], Cmd:[0X02] for I2C
Jan 08 21:20:56 $HOST ipmid[24987]: I2C_WHITELIST_CHECK is disabled, do not populate whitelist
Jan 08 21:20:56 $HOST ipmid[24987]: Registering OEM:[0X00C2CF], Cmd:[0X04] for Manual Zone Control
Jan 08 21:20:56 $HOST systemd[1]: Started Phosphor Inband IPMI.
Jan 08 21:20:56 $HOST ipmid[24987]: Loading whitelist filter
Jan 08 21:20:56 $HOST ipmid[24987]: Set restrictedMode = true
(reverse-i-search)`ipmi': systemctl status phosphor-^Cmi-host

$ ipmitool mc info
Device ID                 : 32
Device Revision           : 1
Firmware Revision         : 0.00
IPMI Version              : 2.0
Manufacturer ID           : 7244
Manufacturer Name         : Quanta Computer Inc.
Product ID                : 14426 (0x385a)
Product Name              : Unknown (0x385A)
Device Available          : yes
Provides Device SDRs      : yes
Additional Device Support :
    Sensor Device
    SEL Device
    FRU Inventory Device
    Chassis Device
Aux Firmware Rev Info     :
    0x00
    0x00
    0x00
    0x00
```

Change-Id: I372c9433a274bc633a24d213b7a1bc205531e33d
Signed-off-by: Willy Tu <wltu@google.com>
diff --git a/chassishandler.cpp b/chassishandler.cpp
index 737d3d2..9b2eb2a 100644
--- a/chassishandler.cpp
+++ b/chassishandler.cpp
@@ -1833,8 +1833,8 @@
 ipmi::RspType<ipmi::message::Payload>
     ipmiChassisGetSysBootOptions(ipmi::Context::ptr ctx,
                                  uint7_t bootOptionParameter, bool reserved1,
-
-                                 uint8_t setSelector, uint8_t blockSelector)
+                                 [[maybe_unused]] uint8_t setSelector,
+                                 [[maybe_unused]] uint8_t blockSelector)
 {
     ipmi::Cc rc;
     if (reserved1)
@@ -1994,8 +1994,7 @@
 }
 
 ipmi::RspType<> ipmiChassisSetSysBootOptions(ipmi::Context::ptr ctx,
-                                             uint7_t parameterSelector,
-                                             bool parameterIsValid,
+                                             uint7_t parameterSelector, bool,
                                              ipmi::message::Payload& data)
 {
     using namespace boot_options;
@@ -2322,9 +2321,10 @@
     return ipmi::responseSuccess(power_policy::allSupport, reserved);
 }
 
-ipmi::RspType<> ipmiSetFrontPanelButtonEnables(
-    ipmi::Context::ptr ctx, bool disablePowerButton, bool disableResetButton,
-    bool disableDiagButton, bool disableSleepButton, uint4_t reserved)
+ipmi::RspType<> ipmiSetFrontPanelButtonEnables(ipmi::Context::ptr ctx,
+                                               bool disablePowerButton,
+                                               bool disableResetButton, bool,
+                                               bool, uint4_t)
 {
     using namespace chassis::internal;