Change the end of SD cart print message from minutes/seconds to hours/minutes.

Marlin/Marlin_main.cpp

         stoptime=millis();
         char time[30];
         unsigned long t=(stoptime-starttime)/1000;
-        int sec,min;
-        min=t/60;
-        sec=t%60;
-        sprintf_P(time, PSTR("%i min, %i sec"),min,sec);
+        int hours, minutes;
+        minutes=(t/60)%60;
+        hours=t/60/60;
+        sprintf_P(time, PSTR("%i hours %i minutes"),hours, minutes);
         SERIAL_ECHO_START;
         SERIAL_ECHOLN(time);
         lcd_setstatus(time);