[builtins] Fix the typo in the preprocessor check
This was introduced in r359413.
#if defined(__ELF__) || defined(__MINGW32__) || defined(__wasm__)
#define COMPILER_RT_ALIAS(name, aliasname) \
COMPILER_RT_ABI __typeof(name) aliasname __attribute__((__alias__(#name)));
-#elif defines(__MACH__)
+#elif defined(__MACH__)
#define COMPILER_RT_ALIAS(name, aliasname) \
__asm__(".globl " SYMBOL_NAME(aliasname)); \
__asm__(SYMBOL_NAME(aliasname) " = " SYMBOL_NAME(name)) \
