x86: Disable -mforce-indirect-call for PIC in 32-bit mode

-mforce-indirect-call generates invalid instruction in 32-bit MI thunk
since there are no available scratch registers in 32-bit PIC mode.
Disable -mforce-indirect-call for PIC in 32-bit mode when generating
MI thunk.

gcc/

	PR target/105980
	* config/i386/i386.cc (x86_output_mi_thunk): Disable
	-mforce-indirect-call for PIC in 32-bit mode.

gcc/testsuite/

	PR target/105980
	* g++.target/i386/pr105980.C: New test.