*: merge some common strings

text   data    bss    dec    hexfilename
 838650   8009      0 846659  ceb43busybox_old
 838519   8009      0 846528  ceac0busybox_unstripped

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

coreutils/install.c

@@ -50,7 +50,7 @@ static void setdefaultfilecon(const char *path)
 
 	if (lsetfilecon(path, scontext) < 0) {
 		if (errno != ENOTSUP) {
-			bb_perror_msg("warning: failed to change context"
+			bb_perror_msg("warning: can't change context"
 					" of %s to %s", path, scontext);
 		}
 	}