CMakeLists: Remove all redundant warnings

These are already explicitly or implicitly set in src/CMakeLists.txt

src/shader_recompiler/CMakeLists.txt

@@ -242,23 +242,17 @@ if (MSVC)
     target_compile_options(shader_recompiler PRIVATE
         /W4
         /WX
-        /we4018 # 'expression' : signed/unsigned mismatch
+
+        /we4242 # 'identifier': conversion from 'type1' to 'type2', possible loss of data
         /we4244 # 'argument' : conversion from 'type1' to 'type2', possible loss of data (floating-point)
         /we4245 # 'conversion' : conversion from 'type1' to 'type2', signed/unsigned mismatch
         /we4254 # 'operator': conversion from 'type1:field_bits' to 'type2:field_bits', possible loss of data
-        /we4267 # 'var' : conversion from 'size_t' to 'type', possible loss of data
-        /we4305 # 'context' : truncation from 'type1' to 'type2'
         /we4800 # Implicit conversion from 'type' to bool. Possible information loss
         /we4826 # Conversion from 'type1' to 'type2' is sign-extended. This may cause unexpected runtime behavior.
     )
 else()
     target_compile_options(shader_recompiler PRIVATE
-        -Werror
         -Werror=conversion
-        -Werror=ignored-qualifiers
-        $<$<CXX_COMPILER_ID:GNU>:-Werror=unused-but-set-parameter>
-        $<$<CXX_COMPILER_ID:GNU>:-Werror=unused-but-set-variable>
-        -Werror=unused-variable
 
         # Bracket depth determines maximum size of a fold expression in Clang since 9c9974c3ccb6.
         # And this in turns limits the size of a std::array.