clover: Fix build with llvm-12.

Fix build error after LLVM commit c495dfe0268b ("[clang][cli] NFC:
Decrease the scope of ParseLangArgs parameters").

../src/gallium/frontends/clover/llvm/invocation.cpp: In function ‘std::unique_ptr<clang::CompilerInstance> {anonymous}::create_compiler_instance(const clover::device&, const string&, const std::vector<std::__cxx11::basic_string<char> >&, std::string&)’:
../src/gallium/frontends/clover/llvm/invocation.cpp:252:55: error: cannot convert ‘clang::PreprocessorOptions’ to ‘std::vector<std::__cxx11::basic_string<char> >&’
  252 |                                 c->getPreprocessorOpts(),
      |                                 ~~~~~~~~~~~~~~~~~~~~~~^~
      |                                                       |
      |                                                       clang::PreprocessorOptions

Closes: #4114
Signed-off-by: Karol Herbst <kherbst@redhat.com>
Reviewed-by: Francisco Jerez <currojerez@riseup.net>
Part-of: <!8543>
36 jobs for !8543 with fix-clover-llvm-12 in 4 minutes and 34 seconds (queued for 2 seconds)
latest detached
Status Job ID Name Coverage
  Sanity
passed #7684634
sanity

00:00:09

 
  Container
passed #7684640
aarch64
arm_build

00:00:18

passed #7684642
arm_test-base

00:00:18

passed #7684644
windows shell 1809 mesa
windows_build_vs2019

00:00:10

passed #7684636
x86_build-base

00:00:16

passed #7684638
x86_test-base

00:00:16

 
  Container 2
passed #7684658
android_build

00:00:16

passed #7684664
arm64_test

00:00:14

passed #7684665
armhf_test

00:00:23

passed #7684653
i386_build

00:00:22

passed #7684646
kernel+rootfs_amd64

00:00:13

passed #7684648
aarch64
kernel+rootfs_arm64

00:01:15

passed #7684650
aarch64
kernel+rootfs_armhf

00:00:11

passed #7684655
ppc64el_build

00:00:17

passed #7684657
s390x_build

00:00:23

passed #7684651
x86_build

00:00:17

passed #7684660
x86_test-gl

00:00:17

passed #7684662
x86_test-vk

00:00:23

 
  Meson X86 64
passed #7684676
meson-clang

00:02:12

passed #7684678
meson-clover

00:02:46

passed #7684671
meson-clover-testing

00:01:58

passed #7684672
gstreamer
meson-gallium

00:02:39

passed #7684674
meson-release

00:01:01

passed #7684667
meson-testing

00:01:03

passed #7684669
meson-testing-asan

00:01:59

passed #7684679
meson-vulkan

00:01:12

 
  Build Misc
passed #7684681
meson-android

00:00:43

passed #7684685
aarch64
meson-arm64

00:01:51

passed #7684687
aarch64
meson-arm64-asan

00:03:31

passed #7684689
aarch64
meson-arm64-build-test

00:01:27

passed #7684683
aarch64
meson-armhf

00:01:58

passed #7684691
meson-i386

00:02:05

passed #7684697
meson-mingw32-x86_64

00:02:20

passed #7684695
kvm
meson-ppc64el

00:02:11

passed #7684693
kvm
meson-s390x

00:02:47

 
  Software Renderer
passed #7684699
llvmpipe-piglit-cl

00:01:46