conf: extend load_for_all_cards hook (id/value table)

For the per-card configuration, add possibility to define
card number -> card driver link table.

Example:

  cards.0 'cards.USB-Audio'
  cards.1 'cards.USB-Audio'
  cards.2 'cards.HDA-Intel'
  cards.3 'cards.USB-Audio'

Signed-off-by: Jaroslav Kysela <perex@perex.cz>

src/conf/alsa.conf

@@ -67,6 +67,21 @@ cards.@hooks [
 				]
 			}
 		]
+		table {
+			id {
+				@func concat
+				strings [
+					{ @func private_integer }
+				]
+			}
+			value {
+				@func concat
+				strings [
+					"cards."
+					{ @func private_string }
+				]
+			}
+		}
 		errors false
 	}
 ]