ors: Implement 'twrp format data' to format the data partition

Change-Id: Ic01685602a47d0b468616e3d5c3f26a44313cdc8
(cherry picked from commit 3b3bd12be11bd859a5f65bb1e8c71136044b3ad3)
diff --git a/orscmd/orscmd.cpp b/orscmd/orscmd.cpp
index 773bef7..8264a77 100755
--- a/orscmd/orscmd.cpp
+++ b/orscmd/orscmd.cpp
@@ -43,6 +43,7 @@
 	printf("  backup <SDCRBAEM> [backupname]\n");
 	printf("  restore <SDCRBAEM> [backupname]\n");
 	printf("  wipe <partition name>\n");
+	printf("  format data\n");
 	printf("  sideload\n");
 	printf("  set <variable> [value]\n");
 	printf("  decrypt <password> [USER ID]\n");