compiler.h: remove duplicated uninitialized_var

Since clang has a different definition for uninitialized_var
it will complain that it is redefined in include/compiler.h.
Since these are already defined in linux/compiler.h just remove
this instance.

Cc: Masahiro Yamada <yamada.m@jp.panasonic.com>
Cc: Tom Rini <trini@ti.com>
Signed-off-by: Jeroen Hofstee <jeroen@myspectrum.nl>

include/compiler.h

@@ -129,9 +129,6 @@ typedef unsigned long int uintptr_t;
 
 #endif /* USE_HOSTCC */
 
-/* compiler options */
-#define uninitialized_var(x)		x = x
-
 #define likely(x)	__builtin_expect(!!(x), 1)
 #define unlikely(x)	__builtin_expect(!!(x), 0)