b43: Fix TBTT and PU timings

This fixes some timings for pre-TBTT and synthetic PU.

Signed-off-by: Michael Buesch <mb@bu3sch.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/b43/b43.h b/drivers/net/wireless/b43/b43.h
index ef8ae38..e478799 100644
--- a/drivers/net/wireless/b43/b43.h
+++ b/drivers/net/wireless/b43/b43.h
@@ -111,6 +111,7 @@
 #define B43_MMIO_GPIO_MASK		0x49E
 #define B43_MMIO_TSF_CFP_START_LOW	0x604
 #define B43_MMIO_TSF_CFP_START_HIGH	0x606
+#define B43_MMIO_TSF_CFP_PRETBTT	0x612
 #define B43_MMIO_TSF_0			0x632	/* core rev < 3 only */
 #define B43_MMIO_TSF_1			0x634	/* core rev < 3 only */
 #define B43_MMIO_TSF_2			0x636	/* core rev < 3 only */