Introduce a type "chipaddr" to abstract the offsets within flash regions

Use chipaddr instead of volatile uint8_t * because when we access chips
in external flashers, they are not accessed via pointers at all.

Benefits: This allows us to differentiate between volatile machine
memory accesses and flash chip accesses. It also enforces usage
of chip_{read,write}[bwl] to access flash chips, so nobody will
unintentionally use pointers to access chips anymore. Some unneeded
casts are removed as well. Grepping for chip operations and machine
memory operations doesn't yield any false positives anymore.

Compile tested on 32 bit and 64 bit Linux.

Corresponding to flashrom svn r519.

Signed-off-by: Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006@gmx.net>
Acked-by: Uwe Hermann <uwe@hermann-uwe.de>
diff --git a/m29f002.c b/m29f002.c
index 040cd2a..78cdc75 100644
--- a/m29f002.c
+++ b/m29f002.c
@@ -22,7 +22,7 @@
 
 int erase_m29f002(struct flashchip *flash)
 {
-	volatile uint8_t *bios = flash->virtual_memory;
+	chipaddr bios = flash->virtual_memory;
 	chip_writeb(0xaa, bios + 0x555);
 	chip_writeb(0x55, bios + 0xaaa);
 	chip_writeb(0x80, bios + 0x555);
@@ -34,8 +34,8 @@
 	return 0;
 }
 
-static void rewrite_block(volatile uint8_t *bios, uint8_t *src,
-			  volatile uint8_t *dst, int size)
+static void rewrite_block(chipaddr bios, uint8_t *src,
+			  chipaddr dst, int size)
 {
 	/* erase */
 	chip_writeb(0xaa, bios + 0x555);
@@ -59,7 +59,7 @@
 	}
 }
 
-static void do_block(volatile uint8_t *bios, uint8_t *src, int i,
+static void do_block(chipaddr bios, uint8_t *src, int i,
 		     unsigned long start, int size)
 {
 	printf("%d at address: 0x%08lx", i, start);
@@ -70,7 +70,7 @@
 int write_m29f002t(struct flashchip *flash, uint8_t *buf)
 {
 	int i, page_size = flash->page_size;
-	volatile uint8_t *bios = flash->virtual_memory;
+	chipaddr bios = flash->virtual_memory;
 
 	/* M29F002(N)T has 7 blocks. From bottom to top their sizes are:
 	 * 64k 64k 64k 32k 8k 8k 16k
@@ -92,7 +92,7 @@
 int write_m29f002b(struct flashchip *flash, uint8_t *buf)
 {
 	int i = 0, page_size = flash->page_size;
-	volatile uint8_t *bios = flash->virtual_memory;
+	chipaddr bios = flash->virtual_memory;
 
 	/* M29F002B has 7 blocks. From bottom to top their sizes are:
 	 * 16k 8k 8k 32k 64k 64k 64k