Use struct flashctx instead of struct flashchip for flash chip access

Struct flashchip is used only for the flashchips array and for
operations which do not access hardware, e.g. printing a list of
supported flash chips.

struct flashctx (flash context) contains all data available in
struct flashchip, but it also contains runtime information like
mapping addresses. struct flashctx is expected to grow additional
members over time, a prime candidate being programmer info.
struct flashctx contains all of struct flashchip with identical
member layout, but struct flashctx has additional members at the end.

The separation between struct flashchip/flashctx shrinks the memory
requirement of the big flashchips array and allows future extension
of flashctx without having to worry about bloat.

Corresponding to flashrom svn r1473.

Signed-off-by: Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006@gmx.net>
Acked-by: Michael Karcher <flashrom@mkarcher.dialup.fu-berlin.de>
diff --git a/stm50flw0x0x.c b/stm50flw0x0x.c
index f3fc4d8..65d520d 100644
--- a/stm50flw0x0x.c
+++ b/stm50flw0x0x.c
@@ -36,7 +36,7 @@
  * The ST M50FLW080B and STM50FLW080B chips have to be unlocked,
  * before you can erase them or write to them.
  */
-static int unlock_block_stm50flw0x0x(struct flashchip *flash, int offset)
+static int unlock_block_stm50flw0x0x(struct flashctx *flash, int offset)
 {
 	chipaddr wrprotect = flash->virtual_registers + 2;
 	static const uint8_t unlock_sector = 0x00;
@@ -79,7 +79,7 @@
 	return 0;
 }
 
-int unlock_stm50flw0x0x(struct flashchip *flash)
+int unlock_stm50flw0x0x(struct flashctx *flash)
 {
 	int i;
 
@@ -94,7 +94,7 @@
 }
 
 /* This function is unused. */
-int erase_sector_stm50flw0x0x(struct flashchip *flash, unsigned int sector, unsigned int sectorsize)
+int erase_sector_stm50flw0x0x(struct flashctx *flash, unsigned int sector, unsigned int sectorsize)
 {
 	chipaddr bios = flash->virtual_memory + sector;