p54: enhance firmware parser to reduce memory waste

This patch greatly reduces one of biggest memory waste in the driver.

The firmware headers provides the right values for extra head-/tailroom
and mtu size which are usually much lower than the old hardcoded ones.

Signed-off-by: Christian Lamparter <chunkeey@web.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/p54/p54common.h b/drivers/net/wireless/p54/p54common.h
index a79c1a1..5f2af51 100644
--- a/drivers/net/wireless/p54/p54common.h
+++ b/drivers/net/wireless/p54/p54common.h
@@ -29,6 +29,17 @@
 	__le16 top_compat;
 } __attribute__((packed));
 
+struct bootrec_desc {
+	__le16 modes;
+	__le16 flags;
+	__le32 rx_start;
+	__le32 rx_end;
+	u8 headroom;
+	u8 tailroom;
+	u8 unimportant[6];
+	u8 rates[16];
+} __attribute__((packed));
+
 #define BR_CODE_MIN			0x80000000
 #define BR_CODE_COMPONENT_ID		0x80000001
 #define BR_CODE_COMPONENT_VERSION	0x80000002