[MELT] Fixing compilation process

[Alexandre Lissy <alissy at mandriva dot com>]

Hello,

I'm submitting those patches that deals with gcc's melt branch. Their
purpose is to fix the compilation process for two issues that I have
spotted while preparing RPMs for Mandriva:
 - We (I don't know why) have -Wp,-D_FORTIFY_SOURCE=2 that gets in the
   CFLAGS, and that's grabbed by MELT to be given to cc1 process.
   However, this provokes an error, as -Wp,-D_FORFITY_SOURCE=2 is said
   to be valid for the driver but not for cc1. Therefore, the fix I
   propose is to strip any reference to -Wp,-D_FORTIFY_SOURCE=2 in
   CFLAGS that melt passes to cc1 directly.
 - We also, in the same build process, passes -pipe directly to cc1.
   This results in the same errors, therefore the proposed patch also
   removes -pipe from flags for cc1.
This is it for the first patch.

 - Another issue is that while building melt modules, some paths are
   constructed with double slashes. It's bogus for RPM's debugedit, so I
   propose a patch that removes unnecessary slashes from the build
   process.
This is for the second patch

 - Latest patch is a trivial run of 'autogen melt-build.def'.

With those modifications, latest revision of melt-branch is able to
compile (not yet finally packaged, but at least we build!).

And I forgot to add that we are covered by agreement RT 319903.