powerpc/audit: Simplify syscall_get_arch()

Make use of is_32bit_task() and CONFIG_CPU_LITTLE_ENDIAN
to simplify syscall_get_arch().
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/4be53b9187a4d8c163968f4d224267e41a7fcc33.1629451479.git.christophe.leroy@csgroup.eu

arch/powerpc/include/asm/syscall.h

@@ -115,16 +115,11 @@ static inline void syscall_set_arguments(struct task_struct *task,
 
 static inline int syscall_get_arch(struct task_struct *task)
 {
-	int arch;
-
-	if (IS_ENABLED(CONFIG_PPC64) && !test_tsk_thread_flag(task, TIF_32BIT))
-		arch = AUDIT_ARCH_PPC64;
+	if (is_32bit_task())
+		return AUDIT_ARCH_PPC;
+	else if (IS_ENABLED(CONFIG_CPU_LITTLE_ENDIAN))
+		return AUDIT_ARCH_PPC64LE;
 	else
-		arch = AUDIT_ARCH_PPC;
-
-#ifdef __LITTLE_ENDIAN__
-	arch |= __AUDIT_ARCH_LE;
-#endif
-	return arch;
+		return AUDIT_ARCH_PPC64;
 }
 #endif	/* _ASM_SYSCALL_H */