Add resize-rootfs recipe to grow rootfs at first boot (#101)

Move rootfs resize logic from systemd bbappend to a dedicated
resize-rootfs recipe.
This avoids overloading systemd with distro-specific services and
provides a cleaner separation of functionality.

Author: lumag

recipes-core/systemd/systemd/growfs-root.conf renamed to recipes-bsp/resize-rootfs/files/growfs-root.conf

@@ -1,14 +1,24 @@
-# Enable systemd-grow-rootfs.service to resize root filesystem at boot
-FILESEXTRAPATHS:append := "${THISDIR}/${BPN}:"
+SUMMARY = "Systemd drop-in service fragment to resize root filesystem at first boot"
+LICENSE = "BSD-3-Clause-Clear"
+LIC_FILES_CHKSUM = "file://${COMMON_LICENSE_DIR}/BSD-3-Clause-Clear;md5=7a434440b651f4a472ca93716d01033a"
+
 SRC_URI += "\
     file://growfs-root.conf \
     file://growfs-root.preset \
 "
 
+inherit features_check systemd
+REQUIRED_DISTRO_FEATURES = "systemd"
+
 do_install:append:qcom() {
     install -Dm 0644 ${WORKDIR}/sources/growfs-root.preset \
             ${D}${systemd_unitdir}/system-preset/98-growfs-root.preset
     install -Dm 0644 ${WORKDIR}/sources/growfs-root.conf \
             ${D}${systemd_unitdir}/system/systemd-growfs-root.service.d/growfs-root.conf
 }
 
+PACKAGES = "${PN}"
+
+FILES:${PN} += "${systemd_unitdir}"
+
+RDEPENDS:${PN} += "e2fsprogs-resize2fs"