MIPS: boot: Cleanup head.S

- Remove .cprestore which 1. doesn't provide any offset, which causes
  LLVM's assembler to choke, and 2. is not actually needed since $gp is
  not written anywhere in this function.

- Remove the .start label since it is already defined within the LEAF()
  macro.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>

arch/mips/boot/compressed/head.S

@@ -16,9 +16,8 @@
 #include <asm/regdef.h>
 
 	.set noreorder
-	.cprestore
-	LEAF(start)
-start:
+
+LEAF(start)
 	/* Save boot rom start args */
 	move	s0, a0
 	move	s1, a1