init: Add support for specifying a services i/o priority

Signed-off-by: San Mehat <san@google.com>
diff --git a/init/keywords.h b/init/keywords.h
index 308118e..254c785 100644
--- a/init/keywords.h
+++ b/init/keywords.h
@@ -75,6 +75,7 @@
     KEYWORD(chmod,       COMMAND, 2, do_chmod)
     KEYWORD(loglevel,    COMMAND, 1, do_loglevel)
     KEYWORD(device,      COMMAND, 4, do_device)
+    KEYWORD(ioprio,      OPTION,  0, 0)
 #ifdef __MAKE_KEYWORD_ENUM__
     KEYWORD_COUNT,
 };