ld testsuite: change unresolved to unsupported/fail

"unresolved" as a test result means runtest returns an error, which
can be confusing when there is no apparent error unless you look in
.log files.  In particular many tests are skipped without reporting an
error if no target C compiler is found, but if a target C compiler is
found but won't compile a testcase for some reason we used to mark the
test as unresolved.  Which is no more worthy of an error than when
lacking a C compiler entirely.

	* testsuite/ld-cdtest/cdtest.exp,
	* testsuite/ld-checks/checks.exp,
	* testsuite/ld-elf/binutils.exp,
	* testsuite/ld-elf/compress.exp,
	* testsuite/ld-elf/dwarf.exp,
	* testsuite/ld-elf/exclude.exp,
	* testsuite/ld-elf/frame.exp,
	* testsuite/ld-elf/indirect.exp,
	* testsuite/ld-elf/linux-x86.exp,
	* testsuite/ld-elf/sec-to-seg.exp,
	* testsuite/ld-elf/tls_common.exp,
	* testsuite/ld-elfcomm/elfcomm.exp,
	* testsuite/ld-elfvers/vers.exp,
	* testsuite/ld-elfvsb/elfvsb.exp,
	* testsuite/ld-elfweak/elfweak.exp,
	* testsuite/ld-ifunc/binutils.exp,
	* testsuite/ld-mips-elf/mips-elf-flags.exp,
	* testsuite/ld-misc/defsym.exp,
	* testsuite/ld-mn10300/mn10300.exp,
	* testsuite/ld-plugin/lto.exp,
	* testsuite/ld-plugin/plugin.exp,
	* testsuite/ld-scripts/align.exp,
	* testsuite/ld-scripts/assert.exp,
	* testsuite/ld-scripts/crossref.exp,
	* testsuite/ld-scripts/defined.exp,
	* testsuite/ld-scripts/extern.exp,
	* testsuite/ld-scripts/log2.exp,
	* testsuite/ld-scripts/map-address.exp,
	* testsuite/ld-scripts/phdrs.exp,
	* testsuite/ld-scripts/phdrs2.exp,
	* testsuite/ld-scripts/script.exp,
	* testsuite/ld-scripts/section-flags.exp,
	* testsuite/ld-scripts/sizeof.exp,
	* testsuite/ld-scripts/weak.exp,
	* testsuite/ld-selective/selective.exp,
	* testsuite/ld-sh/sh.exp,
	* testsuite/ld-shared/shared.exp,
	* testsuite/ld-srec/srec.exp,
	* testsuite/ld-tic6x/tic6x.exp,
	* testsuite/ld-undefined/undefined.exp,
	* testsuite/ld-undefined/weak-undef.exp,
	* testsuite/lib/ld-lib.exp: Don't use unresolved except after
	perror.  Instead report "unsupported" or "fail".