android: panfrost/lib: add pan_cs.c to Makefile.sources

Fixes the following building errors:

FAILED: out/target/product/x86_64/obj/SHARED_LIBRARIES/gallium_dri_intermediates/LINKED/gallium_dri.so
...
ld.lld: error: undefined symbol: pan_emit_tls
>>> referenced by pan_cmdstream.c:2279 (external/mesa/src/gallium/drivers/panfrost/pan_cmdstream.c:2279)
...
ld.lld: error: undefined symbol: pan_emit_fbd
>>> referenced by pan_cmdstream.c:2302 (external/mesa/src/gallium/drivers/panfrost/pan_cmdstream.c:2302)
...
ld.lld: error: undefined symbol: pan_emit_fragment_job
>>> referenced by pan_cmdstream.c:2382 (external/mesa/src/gallium/drivers/panfrost/pan_cmdstream.c:2382)
...
ld.lld: error: undefined symbol: pan_emit_bifrost_tiler_heap
>>> referenced by pan_job.c:718 (external/mesa/src/gallium/drivers/panfrost/pan_job.c:718)
...
ld.lld: error: undefined symbol: pan_emit_bifrost_tiler
>>> referenced by pan_job.c:723 (external/mesa/src/gallium/drivers/panfrost/pan_job.c:723)
...
ld.lld: error: undefined symbol: pan_fbd_has_zs_crc_ext
>>> referenced by pan_job.c:893 (external/mesa/src/gallium/drivers/panfrost/pan_job.c:893)
...
clang-9: error: linker command failed with exit code 1 (use -v to see invocation)

Cc: 21.1 <mesa-stable@lists.freedesktop.org>
Fixes: 387f8c037d ("panfrost: Add various helpers to simplify FB desc emission")
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>.
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/10299>

src/panfrost/Makefile.sources

@@ -37,6 +37,8 @@ lib_FILES := \
         lib/pan_blend.h \
         lib/pan_blitter.c \
         lib/pan_blitter.h \
+        lib/pan_cs.c \
+        lib/pan_cs.h \
         lib/pan_device.h \
         lib/pan_encoder.h \
         lib/pan_format.c \