common/swap: Remove 32-bit ARM path

We don't plan to support host 32-bit ARM execution environments, so this
is essentially dead code.

src/common/swap.h

@@ -71,19 +71,6 @@ inline u32 swap32(u32 _data) {
 inline u64 swap64(u64 _data) {
     return _byteswap_uint64(_data);
 }
-#elif defined(ARCHITECTURE_ARM) && (__ARM_ARCH >= 6)
-inline u16 swap16(u16 _data) {
-    u32 data = _data;
-    __asm__("rev16 %0, %1\n" : "=l"(data) : "l"(data));
-    return (u16)data;
-}
-inline u32 swap32(u32 _data) {
-    __asm__("rev %0, %1\n" : "=l"(_data) : "l"(_data));
-    return _data;
-}
-inline u64 swap64(u64 _data) {
-    return ((u64)swap32(_data) << 32) | swap32(_data >> 32);
-}
 #elif __linux__
 inline u16 swap16(u16 _data) {
     return bswap_16(_data);