LIBPATHFLAG quoting

[Michal Suchanek]

Hello

There has been upgrade from autoconf 2.60 to 2.62 on OS X which leads
to ruby failing to build.

All linking tests fail which results in broken dl extension
segfaulting during tests. Some C extensions don't build at all.

The tests fail because quoting changed between these versions.

LIBPATHFLAG=' -L"%s"' in configure.in results in -L"../.." on the
linker command line with autoconf 2.60 and in -L\"../..\" with 2.62
and broken build.

My suggestion is to remove the quoting (LIBPATHFLAG=' -L%s' because -I
flags are not quoted anyway so a special character in a directory path
would still break the build.

Thanks

Michal