Re: gas: Move gas_sframe_check to binutils-common.exp

PR ld/33146

Correct TCL errors trying to access error output file in commit
ef7a634dc01d.  In fact, get rid of the output file test entirely since
gas exit status is sufficient.

Also there is no need to firstly check for ELF support.

Set check_as_sframe_result, and remove ld-lib.exp check_as_sframe.