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/linux_spi.c b/linux_spi.c
index 44a2fcd..3720823 100644
--- a/linux_spi.c
+++ b/linux_spi.c
@@ -36,9 +36,9 @@
 static int linux_spi_shutdown(void *data);
 static int linux_spi_send_command(unsigned int writecnt, unsigned int readcnt,
 			const unsigned char *txbuf, unsigned char *rxbuf);
-static int linux_spi_read(struct flashchip *flash, uint8_t *buf,
+static int linux_spi_read(struct flashctx *flash, uint8_t *buf,
 			  unsigned int start, unsigned int len);
-static int linux_spi_write_256(struct flashchip *flash, uint8_t *buf,
+static int linux_spi_write_256(struct flashctx *flash, uint8_t *buf,
 			       unsigned int start, unsigned int len);
 
 static const struct spi_programmer spi_programmer_linux = {
@@ -131,13 +131,13 @@
 	return 0;
 }
 
-static int linux_spi_read(struct flashchip *flash, uint8_t *buf,
+static int linux_spi_read(struct flashctx *flash, uint8_t *buf,
 			  unsigned int start, unsigned int len)
 {
 	return spi_read_chunked(flash, buf, start, len, (unsigned)getpagesize());
 }
 
-static int linux_spi_write_256(struct flashchip *flash, uint8_t *buf,
+static int linux_spi_write_256(struct flashctx *flash, uint8_t *buf,
 			       unsigned int start, unsigned int len)
 {
 	return spi_write_chunked(flash, buf, start, len, ((unsigned)getpagesize()) - 4);