package/mesa3d: fix nouveau std::isinf related compile failure

package/mesa3d: fix nouveau std::isinf related compile failure

Activate already existing mesa3d solution for the isinf compile
failure for uclibc based toolchains instead of using a custom
workaround.

- remove 0005-src-gallium-drivers-nouveau-codegen-nv50_ir_ra.cpp-p.patch
- add 0004-c99_math-import-isinf-for-uclibc-based-toolchains.patch

Fixes:
  http://autobuild.buildroot.net/results/cbefc5d4a4fefb674e596400fa1d2698cd89c5b3/
  http://autobuild.buildroot.net/results/dc974da012f53fa4ed3be616f937b0afae423d66/

  ../src/gallium/drivers/nouveau/codegen/nv50_ir_ra.cpp: In member function 'bool nv50_ir::GCRA::simplify()':
  ../src/gallium/drivers/nouveau/codegen/nv50_ir_ra.cpp:1348:19: error: expected unqualified-id before '(' token
            if (std::isinf(bestScore)) {
                     ^

Signed-off-by: Peter Seiderer <ps.report@gmx.net>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>