Detect and resize root partition on QEMU (#414)

To increase the size of the partition you simply increase the size of the image using `truncate -s +200M /path/to/qemu.img` for example and then start QEMU.

More information:
https://github.com/postmarketOS/pmbootstrap/wiki/Common-Qemu-Notes#increase-partition-size

aports/main/postmarketos-mkinitfs/APKBUILD

@@ -1,5 +1,5 @@
 pkgname=postmarketos-mkinitfs
-pkgver=0.3.2
+pkgver=0.3.3
 pkgrel=3
 pkgdesc="Tool to generate initramfs images for postmarketOS"
 url="https://github.com/postmarketOS"
@@ -26,5 +26,5 @@ package() {
 	mkdir -p "$pkgdir/etc/postmarketos-mkinitfs/hooks/"
 }
 sha512sums="95e49eb5e7891d319543165290fb7279733e696db8c768d864d87ef36a20b04e1c4e8a1702a2927e7492ea2e9f3d4fdd83d9ea55811969689b9c2483fb3b44c4  init.sh.in
-64aa05363f79a0cf2319740753b8852f5252a5b35b23fecccb131cd77d306cd4c7fe287b2d58cea456f669ff99e20f53cf609703530abf6eda7c958a9e0811d2  init_functions.sh
+2331fe9a89ba58348b41fbfdeb6f4daeff3f6ef161d1b7582c3e900baba377fa9411efa0b052ea5c2ae22f75bc48f6b8f38dafad0bd836a0319906e70482898c  init_functions.sh
 8b61ecc989f32ed49b34463d457e8506b267af9af5a9f42639354506c27e858517a9e954a62c808bbd114fd31c9628e263bb5ed4d7b754c65d4aea33675ca0ad  mkinitfs.sh"

aports/main/postmarketos-mkinitfs/init_functions.sh

@@ -150,6 +150,12 @@ resize_root_partition() {
 			kpartx -afs "$partition_dev"
 		fi
 	fi
+	# Detect and resize root partition on QEMU
+	if [ -z "${partition##"/dev/hda"*}" ]; then
+		echo "Resize root partition ($partition)"
+		parted -s /dev/hda resizepart 2 100%
+		partprobe
+	fi
 }
 
 unlock_root_partition() {