MIPS: Fix preprocessor warnings flaged by GCC 4.4

Signed-off-by: NDavid Daney <ddaney@caviumnetworks.com>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

arch/mips/include/asm/elf.h

@@ -232,7 +232,7 @@ typedef elf_fpreg_t elf_fpregset_t[ELF_NFPREG];
  */
 #ifdef __MIPSEB__
 #define ELF_DATA	ELFDATA2MSB
-#elif __MIPSEL__
+#elif defined(__MIPSEL__)
 #define ELF_DATA	ELFDATA2LSB
 #endif
 #define ELF_ARCH	EM_MIPS