i2c: Use resource_size macro

This replace all instances in the i2c busses tree of
res->end - res->start + 1 with the handy macro resource_size(res)
from ioport.h (coming in from platform_device.h).

This was created with a simple
sed -i -e 's/\([a-z]*\)->end *- *[a-z]*->start *+ *1/resource_size(\1)/g'

Then manually replacing the PXA redefiniton of the same kind
of macro manually. Recompiled some ARM defconfigs I could find to
make a rough test so it shouldn't break anything, though I
couldn't see exactly which configs you need for all the drivers.

Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
diff --git a/drivers/i2c/busses/i2c-at91.c b/drivers/i2c/busses/i2c-at91.c
index 67d9dc5..06e1ecb 100644
--- a/drivers/i2c/busses/i2c-at91.c
+++ b/drivers/i2c/busses/i2c-at91.c
@@ -200,10 +200,10 @@
 	if (!res)
 		return -ENXIO;
 
-	if (!request_mem_region(res->start, res->end - res->start + 1, "at91_i2c"))
+	if (!request_mem_region(res->start, resource_size(res), "at91_i2c"))
 		return -EBUSY;
 
-	twi_base = ioremap(res->start, res->end - res->start + 1);
+	twi_base = ioremap(res->start, resource_size(res));
 	if (!twi_base) {
 		rc = -ENOMEM;
 		goto fail0;
@@ -252,7 +252,7 @@
 fail1:
 	iounmap(twi_base);
 fail0:
-	release_mem_region(res->start, res->end - res->start + 1);
+	release_mem_region(res->start, resource_size(res));
 
 	return rc;
 }
@@ -268,7 +268,7 @@
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	iounmap(twi_base);
-	release_mem_region(res->start, res->end - res->start + 1);
+	release_mem_region(res->start, resource_size(res));
 
 	clk_disable(twi_clk);		/* disable peripheral clock */
 	clk_put(twi_clk);