package/ti-gfx: do not use devmem2 in script

ti-gfx may install a debug script that uses devmem2 but does not select
BR2_PACKAGE_DEVMEM2. Use devmem, instead, already provided by Busybox.

Signed-off-by: Carlos Santos <unixmania@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

package/ti-gfx/esrev.sh

@@ -48,7 +48,8 @@ case $CPUTYPE in
 	devmem 0x48180900 w 0x2
 	devmem 0x48180920 w 0x2
 
-	ES_REVISION="$(devmem2 0x56000014 | sed -e s:0x00010205:6: -e s:0x00010201:3: -e s:0x00010003:2: | tail -n1 | awk -F': ' '{print $2}')"
+	ES_REVISION="$(devmem 0x56000014 | sed -e s:0x00010205:6: \
+		-e s:0x00010201:3: -e s:0x00010003:2:)"
 	;;
 *)
 	echo Unable to determine SGX hardware