sys-boot/os-prober: fix handling of multiple initrd paths

Backport of upstream fix for handling multiple initrd paths like those
needed for Majaro installations.  Still requires changes in grub from
https://savannah.gnu.org/bugs/index.php?47681, if and when it gets merged
upstream.

Package-Manager: Portage-3.0.26, Repoman-3.0.3
Signed-off-by: Peter Levine <plevine457@gmail.com>
Closes: https://github.com/gentoo/gentoo/pull/22513
Signed-off-by: Ben Kohler <bkohler@gentoo.org>

sys-boot/os-prober/files/os-prober-1.79-handle-multiple-initrd-paths.patch

@@ -0,0 +1,35 @@
+Backport handling of multiple initrd paths, like those needed by Manjaro
+installations. Note, it still requires resolution of
+https://savannah.gnu.org/bugs/index.php?47681 on grub's end.
+
+Commit: https://salsa.debian.org/installer-team/os-prober/-/commit/53b920e106f13acf87ef8a275161e20f94feeb8a
+
+--- a/linux-boot-probes/mounted/common/40grub2
++++ b/linux-boot-probes/mounted/common/40grub2
+@@ -78,11 +78,21 @@
+ 				fi
+ 			;;
+ 			initrd)
+-				initrd="$(echo "$2" | sed 's/(.*)//')"
+-				# Initrd same.
+-				if [ "$partition" != "$bootpart" ]; then
+-					initrd="/boot$initrd"
+-				fi
++				shift
++				initrd=""
++				for initrd_path in "$@"; do
++					# sed hack, as above
++					initrd_path="$(echo "$initrd_path" | sed 's/(.*)//')"
++					# Initrd same.
++					if [ "$partition" != "$bootpart" ]; then
++						initrd_path="/boot$initrd_path"
++					fi
++					if [ -z "$initrd" ]; then
++						initrd="$initrd_path"
++					else
++						initrd="$initrd $initrd_path"
++					fi
++				done
+ 			;;
+ 			"}")
+ 				entry_result

sys-boot/os-prober/os-prober-1.79.ebuild

@@ -27,6 +27,7 @@ QA_MULTILIB_PATHS="usr/lib/os-prober/.*"
 
 PATCHES=(
 	"${FILESDIR}"/${PN}-1.79-mdraid-detection.patch
+	"${FILESDIR}"/${PN}-1.79-handle-multiple-initrd-paths.patch
 	"${FILESDIR}"/${PN}-1.79-btrfs-subvolume-detection.patch
 	"${FILESDIR}"/${PN}-1.79-use-fstab-name.patch
 	"${FILESDIR}"/${PN}-1.79-mounted-boot-partition-fix.patch