mips: Add build salt to the vDSO

The vDSO needs to have a unique build id in a similar manner
to the kernel and modules. Use the build salt macro.

Signed-off-by: Bastian Blank <waldi@debian.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

Author: Bastian Blank

arch/mips/vdso/elf.S

@@ -8,13 +8,16 @@
 
 #include <asm/isa-rev.h>
 
+#include <linux/build-salt.h>
 #include <linux/elfnote.h>
 #include <linux/version.h>
 
 ELFNOTE_START(Linux, 0, "a")
 	.long LINUX_VERSION_CODE
 ELFNOTE_END
 
+BUILD_SALT
+
 /*
  * The .MIPS.abiflags section must be defined with the FP ABI flags set
  * to 'any' to be able to link with both old and new libraries.