MIPS: KVM: Drop redundant restore of DDATA_LO

On return from the exit handler to the host (without re-entering the
guest) we restore the saved value of the DDATA_LO register which we use
as a scratch register. However we've already restored it ready for
calling the exit handler so there is no need to do it again, so drop
that code.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim KrÄmář <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/mips/kvm/entry.c

@@ -581,10 +581,6 @@ static void *kvm_mips_build_ret_to_host(void *addr)
 	UASM_i_LW(&p, K1, offsetof(struct kvm_vcpu_arch, host_stack), K1);
 	uasm_i_addiu(&p, K1, K1, -(int)sizeof(struct pt_regs));
 
-	/* Restore host DDATA_LO */
-	UASM_i_LW(&p, K0, offsetof(struct pt_regs, cp0_epc), K1);
-	uasm_i_mtc0(&p, K0, C0_DDATA_LO);
-
 	/*
 	 * r2/v0 is the return code, shift it down by 2 (arithmetic)
 	 * to recover the err code