tpmr: Don't add newline when extending PCR with literal data

tpmr extend with -ic (extend with literal data) was adding a newline,
use echo -n so it only includes the data given in the hash.

Signed-off-by: Jonathon Hall <jonathon.hall@puri.sm>

initrd/bin/tpmr

@@ -26,10 +26,10 @@ tpm2_extend() {
 				index="$2"
 				shift 2;;
 			-ic)
-				hash="`echo $2|sha256sum|cut -d' ' -f1`"
+				hash="$(echo -n "$2"|sha256sum|cut -d' ' -f1)"
 				shift 2;;
 			-if)
-				hash="`sha256sum $2|cut -d' ' -f1`"
+				hash="$(sha256sum "$2"|cut -d' ' -f1)"
 				shift 2;;
 			*)
 				break;;