Fix more sign-compare issues

The one in the `dummyflasher` is a little peculiar. We actually never
knew the type of the `st_size` field in `struct stat`. It happens to
be `signed` in some systems (e.g. DJGPP).

Change-Id: If36ba22606021400b385ea6083eacc7b360c20c5
Signed-off-by: Nico Huber <nico.h@gmx.de>
Reviewed-on: https://review.coreboot.org/c/flashrom/+/35800
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Jacob Garber <jgarber1@ualberta.ca>
Reviewed-by: Patrick Georgi <pgeorgi@google.com>
diff --git a/dediprog.c b/dediprog.c
index fbd6930..e4124b0 100644
--- a/dediprog.c
+++ b/dediprog.c
@@ -1038,7 +1038,7 @@
 			free(device);
 			return 1;
 		}
-		if (usedevice < 0 || usedevice > UINT_MAX) {
+		if (usedevice < 0 || usedevice > INT_MAX) {
 			msg_perr("Error: Value for 'device' is out of range.\n");
 			free(device);
 			return 1;
diff --git a/dummyflasher.c b/dummyflasher.c
index 2d7fa85..b9f6126 100644
--- a/dummyflasher.c
+++ b/dummyflasher.c
@@ -387,7 +387,7 @@
 	if (!stat(emu_persistent_image, &image_stat)) {
 		msg_pdbg("Found persistent image %s, %jd B ",
 			 emu_persistent_image, (intmax_t)image_stat.st_size);
-		if (image_stat.st_size == emu_chip_size) {
+		if ((uintmax_t)image_stat.st_size == emu_chip_size) {
 			msg_pdbg("matches.\n");
 			msg_pdbg("Reading %s\n", emu_persistent_image);
 			if (read_buf_from_file(flashchip_contents, emu_chip_size,
diff --git a/ich_descriptors.c b/ich_descriptors.c
index 6d7b020..120d3fe 100644
--- a/ich_descriptors.c
+++ b/ich_descriptors.c
@@ -421,7 +421,7 @@
 		for (i = 0; i < nm; i++) {
 			size_t j;
 			msg_pdbg2("%-4s", master_names[i]);
-			for (j = 0; j < min(num_regions, 12); j++)
+			for (j = 0; j < (size_t)min(num_regions, 12); j++)
 				msg_pdbg2("  %c%c ",
 					  desc->master.mstr[i].read & (1 << j) ? 'r' : ' ',
 					  desc->master.mstr[i].write & (1 << j) ? 'w' : ' ');
diff --git a/libflashrom.c b/libflashrom.c
index dbc5129..1d8a9ae 100644
--- a/libflashrom.c
+++ b/libflashrom.c
@@ -139,7 +139,7 @@
  */
 struct flashrom_flashchip_info *flashrom_supported_flash_chips(void)
 {
-	int i = 0;
+	unsigned int i = 0;
 	struct flashrom_flashchip_info *supported_flashchips =
 		malloc(flashchips_size * sizeof(*supported_flashchips));