device/dram/lpddr4.c: Remove unused <string.h>

Change-Id: Iba3135178f2d6021702971e4d887e9b4f8afeb76
Signed-off-by: Elyes HAOUAS <ehaouas@noos.fr>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/60556
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
diff --git a/src/device/dram/lpddr4.c b/src/device/dram/lpddr4.c
index 3c686d0..a0c71f2 100644
--- a/src/device/dram/lpddr4.c
+++ b/src/device/dram/lpddr4.c
@@ -4,7 +4,6 @@
 #include <cbmem.h>
 #include <device/device.h>
 #include <device/dram/lpddr4.h>
-#include <string.h>
 #include <memory_info.h>
 #include <smbios.h>
 #include <types.h>