e1000: fix bugs from recent commits

Commit 114d7fc0 "e1000: Rewrite EEPROM checksum error to give more
information" failed to initialize the checksum variable which should
result in random results. Fix that.

Commit 2326a94d caused a ton of "unused variable 'x'" warnings.
Fix these.  While we are at it, remove some bogus parens.

Signed-off-by: Wolfgang Denk <wd@denx.de>
Cc: Kyle Moffett <Kyle.D.Moffett@boeing.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Tested-by: Kyle Moffett <Kyle.D.Moffett@boeing.com>
diff --git a/drivers/net/e1000.h b/drivers/net/e1000.h
index 05f2bce..d8400d4 100644
--- a/drivers/net/e1000.h
+++ b/drivers/net/e1000.h
@@ -62,15 +62,15 @@
 
 /* I/O wrapper functions */
 #define E1000_WRITE_REG(a, reg, value) \
-	(writel((value), ((a)->hw_addr + E1000_##reg)))
+	writel((value), ((a)->hw_addr + E1000_##reg))
 #define E1000_READ_REG(a, reg) \
-	(readl((a)->hw_addr + E1000_##reg))
+	readl((a)->hw_addr + E1000_##reg)
 #define E1000_WRITE_REG_ARRAY(a, reg, offset, value) \
-	(writel((value), ((a)->hw_addr + E1000_##reg + ((offset) << 2))))
+	writel((value), ((a)->hw_addr + E1000_##reg + ((offset) << 2)))
 #define E1000_READ_REG_ARRAY(a, reg, offset) \
-	(readl((a)->hw_addr + E1000_##reg + ((offset) << 2)))
+	readl((a)->hw_addr + E1000_##reg + ((offset) << 2))
 #define E1000_WRITE_FLUSH(a) \
-	do { uint32_t x = E1000_READ_REG(a, STATUS); } while (0)
+	do { E1000_READ_REG(a, STATUS); } while (0)
 
 /* Forward declarations of structures used by the shared code */
 struct e1000_hw;