* exp_ch13.adb, exp_disp.adb, sem_cat.adb, sem_ch10.adb,
	* sem_ch12.adb, sem_ch6.adb, sem_ch7.adb, sem_ch8.adb,
	* sem_prag.adb, sem_util.adb, sem_warn.adb: Use
	Is_Package_Or_Generic_Package instead of hand-crafted tests.

From-SVN: r139191