treewide: convert sed -r to posix -E

Signed-off-by: Kevin Darbyshire-Bryant <ldir@darbyshire-bryant.me.uk>

include/image.mk

@@ -45,7 +45,7 @@ IMG_PREFIX:=$(VERSION_DIST_SANITIZED)-$(IMG_PREFIX_VERNUM)$(IMG_PREFIX_VERCODE)$
 IMG_ROOTFS:=$(IMG_PREFIX)-rootfs
 IMG_COMBINED:=$(IMG_PREFIX)-combined
 IMG_PART_SIGNATURE:=$(shell echo $(SOURCE_DATE_EPOCH)$(LINUX_VERMAGIC) | mkhash md5 | cut -b1-8)
-IMG_PART_DISKGUID:=$(shell echo $(SOURCE_DATE_EPOCH)$(LINUX_VERMAGIC) | mkhash md5 | sed -r 's/(.{8})(.{4})(.{4})(.{4})(.{10})../\1-\2-\3-\4-\500/')
+IMG_PART_DISKGUID:=$(shell echo $(SOURCE_DATE_EPOCH)$(LINUX_VERMAGIC) | mkhash md5 | sed -E 's/(.{8})(.{4})(.{4})(.{4})(.{10})../\1-\2-\3-\4-\500/')
 
 MKFS_DEVTABLE_OPT := -D $(INCLUDE_DIR)/device_table.txt
 

package/base-files/files/lib/upgrade/common.sh

@@ -5,7 +5,7 @@ RAM_ROOT=/tmp/root
 export BACKUP_FILE=sysupgrade.tgz	# file extracted by preinit
 
 [ -x /usr/bin/ldd ] || ldd() { LD_TRACE_LOADED_OBJECTS=1 $*; }
-libs() { ldd $* 2>/dev/null | sed -r 's/(.* => )?(.*) .*/\2/'; }
+libs() { ldd $* 2>/dev/null | sed -E 's/(.* => )?(.*) .*/\2/'; }
 
 install_file() { # <file> [ <file> ... ]
 	local target dest dir