Log Message:
devel/glib: Fix compiler check via pkglint

AUTOFIX: Makefile:35: Replacing "${PKGSRC_COMPILER} == \ 
\"clang\"" with "${PKGSRC_COMPILER:Mclang}".

        The PKGSRC_COMPILER can be a list of chained compilers, e.g. "ccache
        distcc clang". Therefore, comparing it using == or != leads to wrong
        results in these cases.