Re: Only give FDE encoding warnings if --eh-frame-hdr was specified.

Re: Only give FDE encoding warnings if --eh-frame-hdr was specified.

For mips*-linux targets, fixes the following fails.
FAIL: MIPS eh-frame 1, n32
FAIL: MIPS eh-frame 1, n64
FAIL: MIPS eh-frame 2, n32
FAIL: MIPS eh-frame 2, n64

	* testsuite/ld-mips-elf/eh-frame1-n32.d: Pass --eh-frame-hdr to ld.
	* testsuite/ld-mips-elf/eh-frame1-n64.d: Likewise.
	* testsuite/ld-mips-elf/eh-frame2-n32.d: Likewise.
	* testsuite/ld-mips-elf/eh-frame2-n64.d: Likewise.