INT 16,2 - Read Keyboard Flags

	AH = 02


	on return:
	AL = BIOS keyboard flags (located in BIOS Data Area 40:17)

		|7|6|5|4|3|2|1|0|  AL or BIOS Data Area 40:17
		 | | | | | | | `---- right shift key depressed
		 | | | | | | `----- left shift key depressed
		 | | | | | `------ CTRL key depressed
		 | | | | `------- ALT key depressed
		 | | | `-------- scroll-lock is active
		 | | `--------- num-lock is active
		 | `---------- caps-lock is active
		 `----------- insert is active