nand: Calculate SYS_NAND_BLOCK_PAGES (neeĢ SYS_NAND_PAGE_COUNT) automatically

Contrary to what the help message says, this is the number of pages per
block. Calculate it automatically based on SYS_NAND_BLOCK_SIZE and
SYS_NAND_PAGE_SIZE. To better reflect its semantics, rename it to
SYS_NAND_BLOCK_PAGES.

Signed-off-by: Sean Anderson <seanga2@gmail.com>
diff --git a/README b/README
index 60c6b8a..00d4227 100644
--- a/README
+++ b/README
@@ -1191,11 +1191,10 @@
 		Support for a lightweight UBI (fastmap) scanner and
 		loader
 
-		CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
-		CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
-		CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
-		CFG_SYS_NAND_ECCPOS, CFG_SYS_NAND_ECCSIZE,
-		CFG_SYS_NAND_ECCBYTES
+		CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_SIZE,
+		CONFIG_SYS_NAND_OOBSIZE, CONFIG_SYS_NAND_BLOCK_SIZE,
+		CONFIG_SYS_NAND_BAD_BLOCK_POS, CFG_SYS_NAND_ECCPOS,
+		CFG_SYS_NAND_ECCSIZE, CFG_SYS_NAND_ECCBYTES
 		Defines the size and behavior of the NAND that SPL uses
 		to read U-Boot