uefi: amd64: Fix EfiIoPortIn32 copy/paste error

This change fixes a copy/paste error in the AMD64 inline I/O port reads
in the UEFI core.

uefi/archlib/x64/ioport.S

@@ -140,7 +140,6 @@ Return Value:
 FUNCTION(EfiIoPortIn32)
     movl    %edi, %edx              # Get port number in the right register.
     xorl    %eax, %eax              # Clear the upper word.
-    movl    4(%esp), %edx           # Get the I/O port.
     inl     %dx, %eax               # Perform the I/O port read.
     nop                             # Rest a touch.
     retq                            # Return.