Remove android_atomic_swap from mips & mips64.

Looks like this got left behind in mips by mistake, and
84c3e9923108122045d689f1d2412359ad5208eb carried this over to mips64.
Clean up before it wastes any more time...

Change-Id: I6aeaa6e68be81f94065589337e2f7d3483e6e43c
diff --git a/include/cutils/atomic-mips.h b/include/cutils/atomic-mips.h
index f9d3e25..1ed833d 100644
--- a/include/cutils/atomic-mips.h
+++ b/include/cutils/atomic-mips.h
@@ -117,23 +117,6 @@
 
 
 extern ANDROID_ATOMIC_INLINE int32_t
-android_atomic_swap(int32_t new_value, volatile int32_t *ptr)
-{
-    int32_t prev, status;
-    do {
-    __asm__ __volatile__ (
-        "    move %[status], %[new_value]\n"
-        "    ll %[prev], (%[ptr])\n"
-        "    sc %[status], (%[ptr])\n"
-        : [prev] "=&r" (prev), [status] "=&r" (status)
-        : [ptr] "r" (ptr), [new_value] "r" (new_value)
-        );
-    } while (__builtin_expect(status == 0, 0));
-    android_memory_barrier();
-    return prev;
-}
-
-extern ANDROID_ATOMIC_INLINE int32_t
 android_atomic_add(int32_t increment, volatile int32_t *ptr)
 {
     int32_t prev, status;
diff --git a/include/cutils/atomic-mips64.h b/include/cutils/atomic-mips64.h
index 382f209..99bbe3a 100644
--- a/include/cutils/atomic-mips64.h
+++ b/include/cutils/atomic-mips64.h
@@ -169,23 +169,6 @@
 }
 
 extern ANDROID_ATOMIC_INLINE
-int32_t android_atomic_swap(int32_t new_value, volatile int32_t *ptr)
-{
-    int32_t prev, status;
-    do {
-    __asm__ __volatile__ (
-        "    move %[status], %[new_value]\n"
-        "    ll %[prev], (%[ptr])\n"
-        "    sc %[status], (%[ptr])\n"
-        : [prev] "=&r" (prev), [status] "=&r" (status)
-        : [ptr] "r" (ptr), [new_value] "r" (new_value)
-        );
-    } while (__builtin_expect(status == 0, 0));
-    android_memory_barrier();
-    return prev;
-}
-
-extern ANDROID_ATOMIC_INLINE
 int32_t android_atomic_add(int32_t increment, volatile int32_t *ptr)
 {
     int32_t prev, status;