radeon: Build libllvmradeon the right way.

Better build system integration for:
http://cgit.freedesktop.org/mesa/mesa/commit/?id=91a160b
http://cgit.freedesktop.org/mesa/mesa/commit/?id=5b2855b
gallium/targets: Make use of prebuilt libdricommon.la.
Drop support for --enable-static / --disable-shared.
gallium/auxiliary: Build libgallium shared.
Drop last parts of compatibility for the old Mesa build system.
mapi: Build libglapi always shared.
mesa: Build libmesa shared.
Install all internal shared libs to $(libdir)/mesa-$VERSION.
Makefile.am: s:-no-undefined:-Wl,--no-undefined to make it work.
gallium/drivers: Build libs -shared.
glx: Get rid of libglx.la.
gbm: Get rid of libgbm_dri.la.
i915: Conditionally build an i915g driver instead of two i915 drivers.
gallium/auxiliary/draw/draw_decompose_tmp.h: Fix clang warnings.
More scan-build fixes.
freedreno: Make print_sequence a macro to fix clang.
clover: Force gcc and g++ to fix clang builds.
glsl: For my stupidness remove $(VISIBILITY_CFLAGS).

.libs/st_glsl_to_tgsi.o: In function `ir_if':
/home/abuild/rpmbuild/BUILD/Mesa/build/src/mesa/../../../src/glsl/ir.h:796: undefined reference to `vtable for ir_if'
.libs/st_glsl_to_tgsi.o: In function `ir_loop_jump':
/home/abuild/rpmbuild/BUILD/Mesa/build/src/mesa/../../../src/glsl/ir.h:1439: undefined reference to `vtable for ir_loop_jump'
collect2: error: ld returned 1 exit status

A fix must go in "mesa: Build libmesa shared." patch.