clover/core: Fix x86 build

I unintentionally removed this size_t cast, which is required
for std::max to infer its single template arg.

Fixes: f88347cd ("clover/core: Support MSVC")
Closes: #3920
Reviewed-by: Marcin Slusarz <marcin.slusarz@intel.com>
Part-of: <!7905>
38 jobs for !7905 with x86-clover-build-fix in 19 minutes and 19 seconds (queued for 4 seconds)
detached
Status Job ID Name Coverage
  Sanity
passed #5975759
sanity

00:00:32

 
  Container
passed #5975767
aarch64
arm_build

00:00:21

passed #5975769
arm_test-base

00:00:11

passed #5975771
windows shell 1809 mesa
windows_build_vs2019

00:00:11

passed #5975761
x86_build-base

00:00:20

passed #5975765
x86_build_old

00:00:18

passed #5975763
x86_test-base

00:00:17

 
  Container 2
passed #5975787
android_build

00:00:29

passed #5975792
arm64_test

00:00:33

passed #5975781
i386_build

00:00:30

passed #5975774
kernel+rootfs_amd64

00:00:31

passed #5975775
aarch64
kernel+rootfs_arm64

00:00:23

passed #5975777
aarch64
kernel+rootfs_armhf

00:00:23

passed #5975783
ppc64el_build

00:00:19

passed #5975785
s390x_build

00:00:17

passed #5975779
x86_build

00:00:11

passed #5975788
x86_test-gl

00:00:30

passed #5975790
x86_test-vk

00:00:16

 
  Meson X86 64
passed #5975802
meson-clang

00:01:50

passed #5975800
meson-classic

00:02:58

passed #5975804
meson-clover

00:02:21

passed #5975795
meson-clover-testing

00:03:01

passed #5975797
meson-gallium

00:03:51

passed #5975798
meson-release

00:07:04

passed #5975793
meson-testing

00:02:08

passed #5975806
meson-vulkan

00:01:17

 
  Build Misc
passed #5975807
meson-android

00:00:45

passed #5975811
aarch64
meson-arm64

00:01:22

passed #5975813
aarch64
meson-arm64-build-test

00:01:18

passed #5975809
aarch64
meson-armhf

00:01:21

passed #5975819
meson-i386

00:01:48

passed #5975825
meson-mingw32-x86_64

00:02:00

passed #5975823
kvm
meson-ppc64el

00:03:11

passed #5975821
kvm
meson-s390x

00:03:49

passed #5975815
docker windows 1809 mesa
meson-windows-vs2019

00:06:29

passed #5975817
scons-win64

00:04:47

 
  Software Renderer
passed #5975826
llvmpipe-piglit-cl

00:02:41

 
  Layered Backends
passed #5975828
docker windows 1809 mesa
test-d3d12-windows

00:04:30