powerpc: Use is_32bit_task() helper to test 32-bit binary

This patch removes all explicit tests for the TIF_32BIT flag

Signed-off-by: Denis Kirjanov <dkirjanov@kernel.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/kernel/ptrace.c b/arch/powerpc/kernel/ptrace.c
index 11f3cd9..286d978 100644
--- a/arch/powerpc/kernel/ptrace.c
+++ b/arch/powerpc/kernel/ptrace.c
@@ -1681,7 +1681,7 @@
 
 	if (unlikely(current->audit_context)) {
 #ifdef CONFIG_PPC64
-		if (!test_thread_flag(TIF_32BIT))
+		if (!is_32bit_task())
 			audit_syscall_entry(AUDIT_ARCH_PPC64,
 					    regs->gpr[0],
 					    regs->gpr[3], regs->gpr[4],