gimp-gap: build fails with ccache

[raimue (Rainer Müller)]

gimp-gap fails when ccache is used:

FFMPEG sourcetree found at dir: /opt/local/var/macports/build/_Users_raim_src_macports_trunk_dports_graphics_gimp-gap/work/ffmpeg-0.5.2
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Calling FFMPEG configure script options:      --prefix=/opt/local  --extra-cflags=-I/opt/local/include  --extra-ldflags=-L/opt/local/lib  --cc=ccache /usr/bin/gcc-4.2  --enable-shared --enable-static --disable-amd3dnow --disable-amd3dnowext --disable-mmx --disable-mmx2 --disable-sse --disable-ssse3 --enable-nonfree --enable-gpl --disable-ffmpeg --disable-ffplay --disable-ffserver --cc=/usr/bin/gcc-4.2 --arch=x86_64 --enable-bzlib --enable-libmp3lame --enable-libfaac --enable-libfaad --enable-libxvid
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Unknown option "/usr/bin/gcc-4.2".
See ./configure --help for available options.

At first I tried patching the invocation of the configure script to escape the --cc argument, but I did not get it working. So here is a patch to disable ccache in general for this port.

[dbevans (David B. Evans)]

Committed for both gimp-gap and gimp-gap-devel in r72643. Thanks.