tree: Make internal variables static

All these variables are only used in the files they are defined in, so
they can be made static.

Change-Id: I1e55138adef540e9d3a2237aa5b289cb338c0608
Signed-off-by: Jacob Garber <jgarber1@ualberta.ca>
Reviewed-on: https://review.coreboot.org/c/flashrom/+/33747
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Nico Huber <nico.h@gmx.de>
diff --git a/satamv.c b/satamv.c
index 1d3734a..31265ea 100644
--- a/satamv.c
+++ b/satamv.c
@@ -22,8 +22,8 @@
 #include "programmer.h"
 #include "hwaccess.h"
 
-uint8_t *mv_bar;
-uint16_t mv_iobar;
+static uint8_t *mv_bar;
+static uint16_t mv_iobar;
 
 const struct dev_entry satas_mv[] = {
 	/* 88SX6041 and 88SX6042 are the same according to the datasheet. */