Re-add cpu.c under EXTRA_DIST.
Re-add cpu.c under EXTRA_DIST.

The file cpu.c was removed from the explicit source lists in r15427
which meant it wasn't including in the 'make dist' target.


git-svn-id: 8dbf393e6e9ab8d4979d29f9a341a98016792aa6@15433 0101bb08-14d6-0310-b084-bc0e0c8e3800

Distrotech/libtheora,Distrotech/libtheora,Distrotech/libtheora,KTXSoftware/theora,Distrotech/libtheora,Distrotech/libtheora,KTXSoftware/theora,KTXSoftware/theora,KTXSoftware/theora,KTXSoftware/theora