cmake: fix copy/paste typo

CMakeLists.txt

@@ -788,7 +788,7 @@ else()
   endif()
   set(C_WARNINGS "-Waggregate-return -Wnested-externs -Wold-style-definition -Wstrict-prototypes")
   set(CXX_WARNINGS "-Wno-reorder -Wno-missing-field-initializers")
-  try_compile(STATIC_ASSERT_RES "${CMAKE_CURRENT_BINARY_DIR}/static-assert" "${CMAKE_CURRENT_SOURCE_DIR}/cmake/test-static-assert.c" CMAKE_FLAGS -DCMAKE_CXX_STANDARD=11)
+  try_compile(STATIC_ASSERT_RES "${CMAKE_CURRENT_BINARY_DIR}/static-assert" "${CMAKE_CURRENT_SOURCE_DIR}/cmake/test-static-assert.c" CMAKE_FLAGS -DCMAKE_C_STANDARD=11)
   if(STATIC_ASSERT_RES)
     set(STATIC_ASSERT_FLAG "")
   else()