tree: Use <stdio.h> for snprintf

<stdio.h> header is used for input/output operations (such as printf,
scanf, fopen, etc.). Although some input/output functions can manipulate
strings, they do not need to directly include <string.h> because they
are declared independently.

Change-Id: Ibe2a4ff6f68843a6d99cfdfe182cf2dd922802aa
Signed-off-by: Elyes Haouas <ehaouas@noos.fr>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/82665
Reviewed-by: Yidi Lin <yidilin@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/vendorcode/amd/opensil/genoa_poc/ramstage.c

@@ -9,6 +9,7 @@
 #include <cpu/cpu.h>
 #include <device/device.h>
 #include <soc/soc_chip.h>
+#include <stdio.h>
 #include <xSIM-api.h>
 #include "opensil_console.h"
 #include "opensil.h"

src/vendorcode/cavium/bdk/libbdk-dram/bdk-dram-config.c

@@ -37,6 +37,7 @@
 * ARISING OUT OF USE OR PERFORMANCE OF THE SOFTWARE LIES WITH YOU.
 ***********************license end**************************************/
 #include <bdk.h>
+#include <stdio.h>
 #include <string.h>
 #include <libbdk-hal/bdk-config.h>
 #include <libbdk-hal/bdk-l2c.h>

src/vendorcode/cavium/bdk/libbdk-dram/bdk-dram-test.c

@@ -48,6 +48,7 @@
 #include <libbdk-hal/bdk-utils.h>
 #include <libbdk-os/bdk-init.h>
 #include <libbdk-os/bdk-thread.h>
+#include <stdio.h>
 
 /* This code is an optional part of the BDK. It is only linked in
     if BDK_REQUIRE() needs it */

src/vendorcode/cavium/bdk/libbdk-hal/bdk-config.c

@@ -14,6 +14,7 @@
 #include <string.h>
 #include <assert.h>
 #include <lame_string.h>
+#include <stdio.h>
 
 static struct bdk_devicetree_key_value *config_fdt;
 

src/vendorcode/cavium/bdk/libbdk-hal/device/bdk-device.c

@@ -38,6 +38,7 @@
 ***********************license end**************************************/
 #include <bdk.h>
 #include <stdlib.h>
+#include <stdio.h>
 #include <string.h>
 #include "libbdk-arch/bdk-csrs-ap.h"
 #include "libbdk-arch/bdk-csrs-pccpf.h"

src/vendorcode/cavium/bdk/libdram/dram-init-ddr3.c

@@ -43,6 +43,7 @@
 #include "dram-internal.h"
 
 #include <stdlib.h>
+#include <stdio.h>
 #include <string.h>
 #include <libbdk-hal/bdk-config.h>
 #include <libbdk-hal/bdk-l2c.h>

src/vendorcode/google/smbios.c

@@ -2,6 +2,7 @@
 
 #include <boardid.h>
 #include <smbios.h>
+#include <stdio.h>
 #include <string.h>
 
 const char *smbios_mainboard_version(void)