Unsignify lengths and addresses in chip functions and structs

Push those changes forward where needed to prevent new sign
conversion warnings where possible.

Corresponding to flashrom svn r1470.

Signed-off-by: Stefan Tauner <stefan.tauner@alumni.tuwien.ac.at>
Acked-by: Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006@gmx.net>
diff --git a/sst49lfxxxc.c b/sst49lfxxxc.c
index 28f6cd0..c3ef823 100644
--- a/sst49lfxxxc.c
+++ b/sst49lfxxxc.c
@@ -35,7 +35,7 @@
 static int write_lockbits_49lfxxxc(struct flashchip *flash, unsigned char bits)
 {
 	chipaddr registers = flash->virtual_registers;
-	int i, left = flash->total_size * 1024;
+	unsigned int i, left = flash->total_size * 1024;
 	unsigned long address;
 
 	msg_cdbg("\nbios=0x%08lx\n", registers);