[media] Two small string fixes in v4l2-ctrls.c

Fix one typo and use 'Microseconds' instead of 'useconds' in the pre-emphasis
descriptions.

Signed-off-by: Mauro Carvalho Chehab <[e-mail]>

drivers/media/video/v4l2-ctrls.c

···
 	};
 	static const char * const tune_preemphasis[] = {
 		"No Preemphasis",
-		"50 useconds",
-		"75 useconds",
+		"50 Microseconds",
+		"75 Microseconds",
 		NULL,
 	};
 	static const char * const header_mode[] = {
···
 	};
 	static const char * const mpeg4_profile[] = {
 		"Simple",
-		"Adcanved Simple",
+		"Advanced Simple",
 		"Core",
 		"Simple Scalable",
 		"Advanced Coding Efficency",