Patch from Vladimir:
    1) fixed a bug that could crash df, mount, and umount applets if the root
    device name was longer then the word "root" (/dev/loop1 vs /dev/root) -
    2) severl functions needed static declaration in the umount applet
    3) update declaration for function in last_char_is() in libbb
diff --git a/libbb/last_char_is.c b/libbb/last_char_is.c
index 36b695b..ae2d24b 100644
--- a/libbb/last_char_is.c
+++ b/libbb/last_char_is.c
@@ -25,9 +25,9 @@
  * underrun the buffer if the string length is 0.  Also avoids a possible
  * space-hogging inline of strlen() per usage.
  */
-char * last_char_is(char *s, int c)
+char * last_char_is(const char *s, int c)
 {
-	char *sret  = s+strlen(s)-1;
+	char *sret  = (char *)s+strlen(s)-1;
 	if (sret>=s && *sret == c) { 
 		return sret;
 	} else {