x86/asm/entry/64: Remove pointless jump to irq_return

INTERRUPT_RETURN turns into a jmp instruction.  There's no need
for extra indirection.

Signed-off-by: Andy Lutomirski <[email protected]>
Cc: <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Brian Gerst <[email protected]>
Cc: Denys Vlasenko <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Link: http://lkml.kernel.org/r/2f2318653dbad284a59311f13f08cea71298fd7c.1433449436.git.luto@kernel.org
Signed-off-by: Ingo Molnar <[email protected]>

Author: amluto

arch/x86/entry/entry_64.S

@@ -663,8 +663,6 @@ retint_kernel:
 restore_c_regs_and_iret:
 	RESTORE_C_REGS
 	REMOVE_PT_GPREGS_FROM_STACK 8
-
-irq_return:
 	INTERRUPT_RETURN
 
 ENTRY(native_iret)
@@ -1432,7 +1430,7 @@ nmi_restore:
 
 	/* Clear the NMI executing stack variable */
 	movq $0, 5*8(%rsp)
-	jmp irq_return
+	INTERRUPT_RETURN
 END(nmi)
 
 ENTRY(ignore_sysret)