[ALSA] Add Mic capture support.

CA0106 driver
Notes: This adds a new mixer item to switch between Mic and Line-in.

Signed-off-by: James Courtier-Dutton <James@superbug.co.uk>
diff --git a/sound/pci/ca0106/ca0106.h b/sound/pci/ca0106/ca0106.h
index 67e56a5..beac9da 100644
--- a/sound/pci/ca0106/ca0106.h
+++ b/sound/pci/ca0106/ca0106.h
@@ -589,6 +589,7 @@
 	u32 spdif_bits[4];             /* s/pdif out setup */
 	int spdif_enable;
 	int capture_source;
+	int capture_mic_line_in;
 
 	struct snd_dma_buffer buffer;
 };