main/mesa-pvr-dri-classic: bump _llvmver to 11 (MR 2049)

[ci:skip-build]: already built successfully in CI

main/mesa-pvr-dri-classic/APKBUILD

@@ -2,13 +2,13 @@
 
 pkgname=mesa-pvr-dri-classic
 pkgver=20.3.2
-pkgrel=0
+pkgrel=1
 _tag=mesa-pvr-20.3.2
 pkgdesc="Mesa DRI OpenGL library with PowerVR patches"
 url="https://github.com/xc-racer99/mesa-pvr/"
 arch="armhf armv7 aarch64"
 license="MIT SGI-B-2.0 BSL-1.0"
-_llvmver=10
+_llvmver=11
 depends_dev="
 	libdrm-dev
 	libxext-dev
@@ -64,6 +64,8 @@ build() {
 
 	python3 bin/git_sha1_gen.py --output include/git_sha1.h
 
+	# Reasoning for gallium-drivers="swrast":
+	# https://gitlab.com/postmarketOS/pmaports/-/merge_requests/2049#note_543436715
 	abuild-meson \
 		-Ddri-drivers-path=$_dri_driverdir \
 		-Dgallium-drivers="swrast" \