revert '-Wl' prefixing to *_LD_OPTS
revert '-Wl' prefixing to *_LD_OPTS

This reverts f48f5a9ebf384e1e157b7b413e1d779f4289ddd2

The prefixing does not work as comma
is stripped by $(addprefix) macro:

The following call
    $$(addprefix -optl-Wl, $$($1_$2_$3_ALL_LD_OPTS))

prefixes options with "-optl-Wl" not with "-optl-Wl,"

The simplest breakage can be seen by adding
    SRC_LD_OPTS += -O1
to mk/build.mk:

  <no location info>: error:
    Warning: Couldn't figure out linker information!
             Make sure you're using GNU ld, GNU gold
             or the built in OS X linker, etc.
  gcc: error: unrecognized command line option '-Wl-O1'

Another problem with original change is loss of ability
to pass options to gcc as a linker driver, for example:
    SRC_LD_OPTS += -flto

Signed-off-by: Sergei Trofimovich <df7d2cee2e7ececeb2368216a0f9d0537fd32149@google.com>
(cherry picked from commit a6657bd0d6b9949098021d89ed3cd8a943bdd3b6)

GaloisInc/halvm-ghc,GaloisInc/halvm-ghc,GaloisInc/halvm-ghc,GaloisInc/halvm-ghc,GaloisInc/halvm-ghc,GaloisInc/halvm-ghc,GaloisInc/halvm-ghc