linux-postmarketos-qcom-msm8998: V=1 workaround

Until these kernels are upgraded to >= 6.2, we need V=1 to work around silent make output leading to failing builds (see #1990 (closed)).

Currently both fail to build on bpo.

device/testing/linux-postmarketos-qcom-msm8998/APKBUILD

@@ -4,7 +4,7 @@
 _flavor="postmarketos-qcom-msm8998"
 pkgname=linux-$_flavor
 pkgver=6.0
-pkgrel=1
+pkgrel=2
 _commit="90169e6e9fee29fae14aeac0a905246be5ce6304"
 pkgdesc="Mainline Kernel fork for MSM8998 devices"
 arch="aarch64"
@@ -41,8 +41,9 @@ prepare() {
 
 build() {
 	unset LDFLAGS
+	# V=1: workaround for pma#1990, remove after upgrading to >= 6.2
 	make ARCH="$_carch" CC="${CC:-gcc}" \
-		KBUILD_BUILD_VERSION="$((pkgrel + 1))-$_flavor"
+		KBUILD_BUILD_VERSION="$((pkgrel + 1))-$_flavor" V=1
 }
 
 package() {