iwlagn: add bt prio_boost to .cfg

Use .cfg to configure the default bt priority boost value;
the default bt priority boost is 0xf0

Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/iwlwifi/iwl-commands.h b/drivers/net/wireless/iwlwifi/iwl-commands.h
index b45882a..e742f99 100644
--- a/drivers/net/wireless/iwlwifi/iwl-commands.h
+++ b/drivers/net/wireless/iwlwifi/iwl-commands.h
@@ -2409,7 +2409,7 @@
 
 #define IWL6000G2B_BT_PRIO_BOOST_MAX		0xFF
 #define IWL6000G2B_BT_PRIO_BOOST_MIN		0x00
-#define IWL6000G2B_BT_PRIO_BOOST_DEFAULT	0x00
+#define IWL6000G2B_BT_PRIO_BOOST_DEFAULT	0xF0
 
 #define IWL6000G2B_BT_MAX_KILL_DEFAULT		5