[CMAKE] Some options are only supported by GCC, don't use them for clang

These are (so far):
-Wno-format-overflow
-Wno-nonnull-compare
-Wno-old-style-declaration
-Wno-unused-but-set-variable

drivers/storage/class/classpnp/CMakeLists.txt

@@ -42,7 +42,11 @@ target_compile_definitions(classpnp PRIVATE
     CLASS_GLOBAL_BUFFERED_DEBUG_PRINT_BUFFERS=512)
 
 if(GCC)
-    target_compile_options(classpnp PRIVATE -Wno-unused-but-set-variable -Wno-pointer-to-int-cast -Wno-switch)
+    target_compile_options(classpnp PRIVATE -Wno-pointer-to-int-cast -Wno-switch)
+endif()
+
+if(CMAKE_C_COMPILER_ID STREQUAL "GNU")
+    target_compile_options(classpnp PRIVATE -Wno-unused-but-set-variable)
 endif()
 
 set_module_type(classpnp kernelmodedriver)

drivers/storage/class/disk_new/CMakeLists.txt

@@ -21,7 +21,11 @@ if(USE_CLANG_CL OR (NOT MSVC))
 endif()
 
 if(GCC)
-    target_compile_options(disk PRIVATE -Wno-unused-but-set-variable -Wno-pointer-to-int-cast -Wno-switch)
+    target_compile_options(disk PRIVATE -Wno-pointer-to-int-cast -Wno-switch)
+endif()
+
+if(CMAKE_C_COMPILER_ID STREQUAL "GNU")
+    target_compile_options(disk PRIVATE -Wno-unused-but-set-variable)
 endif()
 
 set_module_type(disk kernelmodedriver)

drivers/storage/ide/uniata/CMakeLists.txt

@@ -25,11 +25,13 @@ if(USE_CLANG_CL OR (NOT MSVC))
     target_compile_options(uniata PRIVATE "-Wno-narrowing")
     if(USE_CLANG_CL)
         target_compile_options(uniata PRIVATE "-Wno-unused-const-variable")
-    else()
-        target_compile_options(uniata PRIVATE "-Wno-unused-but-set-variable")
     endif()
 endif()
 
+if(CMAKE_C_COMPILER_ID STREQUAL "GNU")
+    target_compile_options(uniata PRIVATE -Wno-unused-but-set-variable)
+endif()
+
 add_pch(uniata stdafx.h SOURCE)
 set_module_type(uniata kernelmodedriver)
 add_importlibs(uniata scsiport ntoskrnl hal)