locking/atomic, mips: Use s64 for atomic64

locking/atomic, mips: Use s64 for atomic64

As a step towards making the atomic64 API use consistent types treewide,
let's have the mips atomic64 implementation use s64 as the underlying
type for atomic64_t, rather than long or __s64, matching the generated
headers.

As atomic64_read() depends on the generic defintion of atomic64_t, this
still returns long on 64-bit. This will be converted in a subsequent
patch.

Otherwise, there should be no functional change as a result of this
patch.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aou@eecs.berkeley.edu
Cc: arnd@arndb.de
Cc: bp@alien8.de
Cc: catalin.marinas@arm.com
Cc: davem@davemloft.net
Cc: fenghua.yu@intel.com
Cc: heiko.carstens@de.ibm.com
Cc: herbert@gondor.apana.org.au
Cc: ink@jurassic.park.msu.ru
Cc: linux@armlinux.org.uk
Cc: mattst88@gmail.com
Cc: mpe@ellerman.id.au
Cc: palmer@sifive.com
Cc: paulus@samba.org
Cc: rth@twiddle.net
Cc: tony.luck@intel.com
Cc: vgupta@synopsys.com
Link: https://lkml.kernel.org/r/20190522132250.26499-10-mark.rutland@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>