powerpc/ptrace: Remove duplicate check from pt_regs_check()

"offsetof(struct pt_regs, msr) == offsetof(struct user_pt_regs, msr)"
checked in pt_regs_check() twice in a row. Remove the second check.

Signed-off-by: Denis Efremov <efremov@linux.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210305112807.26299-1-efremov@linux.com

Author: evdenis

arch/powerpc/kernel/ptrace/ptrace.c

@@ -354,8 +354,6 @@ void __init pt_regs_check(void)
 		     offsetof(struct user_pt_regs, nip));
 	BUILD_BUG_ON(offsetof(struct pt_regs, msr) !=
 		     offsetof(struct user_pt_regs, msr));
-	BUILD_BUG_ON(offsetof(struct pt_regs, msr) !=
-		     offsetof(struct user_pt_regs, msr));
 	BUILD_BUG_ON(offsetof(struct pt_regs, orig_gpr3) !=
 		     offsetof(struct user_pt_regs, orig_gpr3));
 	BUILD_BUG_ON(offsetof(struct pt_regs, ctr) !=