Do not truncate office phones in finger's summary listing

When finger is invoked as as "finger username", it produces the
long listing by default, and phones numbers are pretty-printed
by the prphone() function. When invoked as just "finger", the
same pretty-printing happens, but is truncated at 9 characters.
Given the summary listing is already greater than 80 columns,
making it even wider is of no harm.

Approved by:	rpaulo (mentor)
Differential Revision:	https://reviews.freebsd.org/D5638

usr.bin/finger/sprint.c

@@ -149,7 +149,7 @@ sflag_print(void)
 				else if (pn->officephone)
 					(void)printf(" %-7.7s", " ");
 				if (pn->officephone)
-					(void)printf(" %-.9s",
+					(void)printf(" %-.15s",
 					    prphone(pn->officephone));
 			} else
 				(void)printf(" %.*s", MAXHOSTNAME, w->host);