Fixes setting CMAKE_C_COMPILER flag being ignored

CMakeLists.txt

@@ -1,12 +1,14 @@
 cmake_minimum_required(VERSION 3.10)
 
-if (GCC AND (NOT CMAKE_C_COMPILER))
+if (NOT CMAKE_C_COMPILER)
+    if (GCC)
         set(CMAKE_C_COMPILER "gcc")
         set(CMAKE_CXX_COMPILER "g++")
-else()
+    else()
         set(CMAKE_C_COMPILER "clang")
         set(CMAKE_CXX_COMPILER "clang++")
-endif(GCC AND (NOT CMAKE_C_COMPILER))
+    endif(GCC)
+endif(NOT CMAKE_C_COMPILER)
 
 project(PorygonLang)