main/lk2nd: add subpackage for quirky htc-memul (MR 4244)

htc-memul needs a special build with a different scratch address set. So
generalize the build function so we can make multiple builds with
parameters without duplicating too much code.

main/lk2nd/APKBUILD

 # Maintainer: Alexey Minnekhanov <alexeymin@postmarketos.org>
 pkgname=lk2nd
 pkgver=0.15.0
-pkgrel=0
+pkgrel=1
 pkgdesc="Secondary little kernel (lk) bootloader for several Qualcomm devices"
 arch="armv7 aarch64"
 url="https://github.com/msm8916-mainline/lk2nd"
@@ -26,12 +26,13 @@ if [ "$CARCH" = "armv7" ]; then
 		$subpackages
 		$pkgname-msm8226
 		$pkgname-msm8226-appended:msm8226_appended
+		$pkgname-msm8226-htc-memul:msm8226_htc_memul
 		$pkgname-msm8974
 		$pkgname-msm8974-appended:msm8974_appended
 	"
 fi
 
-build() {
+_build() {
 	# This builds baremetal executable; distro-specific compiler flags
 	#   and optimizations can't be set by build system.
 	unset CFLAGS
@@ -47,10 +48,17 @@ build() {
 	unset PATH
 	export PATH=/usr/sbin:/usr/bin:/sbin:/bin
 
-	make LK2ND_VERSION="$pkgver-r$pkgrel-postmarketos" TOOLCHAIN_PREFIX=arm-none-eabi- lk2nd-msm8916
+	local project="$1"; shift
+
+	make LK2ND_VERSION="$pkgver-r$pkgrel-postmarketos" TOOLCHAIN_PREFIX=arm-none-eabi- "$@" "$project"
+}
+
+build() {
+	_build lk2nd-msm8916
 	if [ "$CARCH" = "armv7" ]; then
-		make LK2ND_VERSION="$pkgver-r$pkgrel-postmarketos" TOOLCHAIN_PREFIX=arm-none-eabi- lk2nd-msm8974
-		make LK2ND_VERSION="$pkgver-r$pkgrel-postmarketos" TOOLCHAIN_PREFIX=arm-none-eabi- lk2nd-msm8226
+		_build lk2nd-msm8974
+		_build lk2nd-msm8226
+		_build lk2nd-msm8226 BOOTLOADER_OUT=htc-memul SCRATCH_ADDR=0x20000000 SCRATCH_ADDR_512MAP=0x20000000 SCRATCH_SIZE_512MAP=0x10000000
 	fi
 }
 
@@ -89,6 +97,11 @@ msm8226_appended() {
 		"$subpkgdir"/boot/lk2nd.img
 }
 
+msm8226_htc_memul() {
+	install -Dm644 "$builddir"/htc-memul/build-lk2nd-msm8226/lk2nd.img \
+		"$subpkgdir"/boot/lk2nd.img
+}
+
 sha512sums="
 60551065ea072257b459629ea2c555933fae97eef08e6bee5904aa3751cb67fa38125f89f8d7e06c6d9438b3783d81da428b3b428e46cf6bd8dae0ee9163c1b5  lk2nd-0.15.0.tar.gz
 "