MIPS: KVM: Fix fpu.S misassembly with r6

__kvm_save_fpu and __kvm_restore_fpu use .set mips64r2 so that they can
access the odd FPU registers as well as the even, however this causes
misassembly of the return instruction on MIPSr6.

Fix by replacing .set mips64r2 with .set fp=64, which doesn't change the
architecture revision.

Signed-off-by: James Hogan <[e-mail]>
Cc: Paolo Bonzini <[e-mail]>
Cc: Radim KrÄmář <[e-mail]>
Cc: Ralf Baechle <[e-mail]>
Cc: [e-mail]
Cc: [e-mail]
Signed-off-by: Paolo Bonzini <[e-mail]>

arch/mips/kvm/fpu.S

···
 #include <asm/mipsregs.h>
 #include <asm/regdef.h>
 
+/* preprocessor replaces the fp in ".set fp=64" with $30 otherwise */
+#undef fp
+
 	.set	noreorder
 	.set	noat
 
 LEAF(__kvm_save_fpu)
 	.set	push
-	.set	mips64r2
 	SET_HARDFLOAT
+	.set	fp=64
 	mfc0	t0, CP0_STATUS
 	sll     t0, t0, 5			# is Status.FR set?
 	bgez    t0, 1f				# no: skip odd doubles
···
 
 LEAF(__kvm_restore_fpu)
 	.set	push
-	.set	mips64r2
 	SET_HARDFLOAT
+	.set	fp=64
 	mfc0	t0, CP0_STATUS
 	sll     t0, t0, 5			# is Status.FR set?
 	bgez    t0, 1f				# no: skip odd doubles