powerpc/asm-offsets: GPR14 is not needed either

Commit aac6a91f ("powerpc/asm: Remove unused symbols in
asm-offsets.c") removed GPR15 to GPR31 but kept GPR14,
probably because it pops up in a couple of comments when doing
a grep.

However, it was never used either, so remove it as well.

Fixes: aac6a91f ("powerpc/asm: Remove unused symbols in asm-offsets.c")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/9881c68fbca004f9ea18fc9473f630e11ccd6417.1615806071.git.christophe.leroy@csgroup.eu

arch/powerpc/kernel/asm-offsets.c

@@ -320,9 +320,6 @@ int main(void)
 	STACK_PT_REGS_OFFSET(GPR11, gpr[11]);
 	STACK_PT_REGS_OFFSET(GPR12, gpr[12]);
 	STACK_PT_REGS_OFFSET(GPR13, gpr[13]);
-#ifndef CONFIG_PPC64
-	STACK_PT_REGS_OFFSET(GPR14, gpr[14]);
-#endif /* CONFIG_PPC64 */
 	/*
 	 * Note: these symbols include _ because they overlap with special
 	 * register names