library: silence the clang warning for 'uptime' module

Reference(s):
proc/uptime.c:191:9: warning: variable 'uphours' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized]

Signed-off-by: Jim Warner <james.warner@comcast.net>

proc/uptime.c

@@ -151,7 +151,7 @@ PROCPS_EXPORT char *procps_uptime_sprint(void)
  */
 PROCPS_EXPORT char *procps_uptime_sprint_short(void)
 {
-    int updecades, upyears, upweeks, updays, uphours, upminutes = 0;
+    int updecades, upyears, upweeks, updays, uphours = 0, upminutes = 0;
     int pos = 3;
     int comma = 0;
     double uptime_secs, idle_secs;