elf: Remove duplicate preprocessor constant definition

Remove duplicate preprocessor constant definition for EF_MIPS_ARCH.

The duplicate was introduced in commit 45506bdd. It placed the
constant EF_MIPS_ARCH in a better place, however it did not remove
the original. This patch removes the original occurrence.
Reviewed-by: NPhilippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Signed-off-by: NAleksandar Markovic <amarkovic@wavecomp.com>

include/elf.h

@@ -61,7 +61,6 @@ typedef int64_t  Elf64_Sxword;
 #define EF_MIPS_ABI		0x0000f000
 #define EF_MIPS_FP64      0x00000200
 #define EF_MIPS_NAN2008   0x00000400
-#define EF_MIPS_ARCH      0xf0000000
 
 /* These constants define the different elf file types */
 #define ET_NONE   0