[Pkg-opencl-devel] oclgrind 15.5-4 ready for upload

[J Price]

I've addressed the libc ::isnan issue (bug #818823).

I've also added a patch to attempt to address the FTBFS on big-endian
systems (bug #807446). I've tested this on a mips qemu system and it
now passes all of the tests. I didn't add a 'Closes #' to the
changelog just in case there's other issues for powerpc/s390x, but
I'll manually close the bug if buildd passes for those architectures.

James