Revert "mesa: Enable asm unconditionally, now that gen_matypes is gone."

This reverts commit 20294dce.

This breaks my chromeos android build.

src/mapi/shared-glapi/e4b98b6@@glapi@sha/.._entry.c.o(.text+0xe): error: undefined reference to '_glapi_tls_Dispatch'

while building src/mapi/shared-glapi/libglapi.so.0.0.0

Fixes: 20294dce "mesa: Enable asm unconditionally, now that gen_matypes is gone."
10 jobs for !1283 with cros-build-fix in 10 minutes and 8 seconds (queued for 3 seconds)
latest detached
Status Job ID Name Coverage
  Containers Build
passed #405929
debian

00:00:19

 
  Build+Test
passed #405931
meson-clang

00:09:49

passed #405935
meson-clover

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passed #405934
meson-main

00:05:26

passed #405930
meson-swr-glvnd

00:02:19

passed #405936
meson-vulkan

00:03:00

passed #405938
scons-llvm

00:02:29

passed #405937
scons-nollvm

00:06:01

passed #405932
scons-swr

00:03:32

passed #405933
scons-win64

00:07:17