[MIPS] Replace __attribute_used__ with __used

Replaces the deprecated __attribute_used__ with __used.  Also makes some
style adjustments to abide by the kernel coding conventions.

Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/kernel/gdb-stub.c b/arch/mips/kernel/gdb-stub.c
index 7bc8820..cb5623a 100644
--- a/arch/mips/kernel/gdb-stub.c
+++ b/arch/mips/kernel/gdb-stub.c
@@ -1099,12 +1099,12 @@
  * malloc is needed by gdb client in "call func()", even a private one
  * will make gdb happy
  */
-static void * __attribute_used__ malloc(size_t size)
+static void __used *malloc(size_t size)
 {
 	return kmalloc(size, GFP_ATOMIC);
 }
 
-static void __attribute_used__ free (void *where)
+static void __used free(void *where)
 {
 	kfree(where);
 }