correct source reference for urldecode

Reference: /n/atom/patch/applied/urldecodeman
Date: Sun Oct  4 02:28:53 CES 2015
Signed-off-by: quanstro@quanstro.net

--- /sys/man/1/urldecode	Sun Oct  4 02:28:37 2015
+++ /sys/man/1/urldecode	Sun Oct  4 02:28:38 2015
@@ -20,9 +20,9 @@
 encodes them.  If there are no arguments, standard input
 is coded.
 .SH SOURCE
-.B /sys/src/cmd/url/urldecode.c
+.B /sys/src/cmd/url/decode.c
 .br
-.B /sys/src/cmd/url/urlencode.c
+.B /sys/src/cmd/url/encode.c
 .SH SEE ALSO
 RFC 3986, 
 .I Uniform Resource Identifier (URI): Generic Syntax