[Bug target/68937] i686: -fno-plt produces wrong code (maybe only with tailcall)

[hjl.tools at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68937

--- Comment #4 from H.J. Lu <hjl.tools at gmail dot com> ---
sibcall_memory_operand shouldn't allow any callee-saved registers
as GOT base register since they must be restored before return.