MdePkg: Support FDT library.

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=4392
Add FDT support in EDK2 by submodule 3rd party libfdt
(https://github.com/devicetree-org/pylibfdt/tree/main/libfdt)
and refer to LibcLib implementation by Pedro.

Cc: Michael D Kinney <michael.d.kinney@intel.com>
Cc: Liming Gao <gaoliming@byosoft.com.cn>
Cc: Zhiguang Liu <zhiguang.liu@intel.com>
Signed-off-by: Benny Lin <benny.lin@intel.com>
Acked-by: Pedro Falcato <pedro.falcato@gmail.com>
Reviewed-by: Michael D Kinney <michael.d.kinney@intel.com>

MdePkg/Library/BaseFdtLib/LibFdtSupport.h

@@ -0,0 +1,99 @@
+/** @file
+  Root include file of C runtime library to support building the third-party
+  libfdt library.
+
+  Copyright (c) 2023, Intel Corporation. All rights reserved.<BR>
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#ifndef FDT_LIB_SUPPORT_H_
+#define FDT_LIB_SUPPORT_H_
+
+#include <Base.h>
+#include <Library/BaseLib.h>
+#include <Library/BaseMemoryLib.h>
+
+typedef UINT8    uint8_t;
+typedef UINT16   uint16_t;
+typedef INT32    int32_t;
+typedef UINT32   uint32_t;
+typedef UINT64   uint64_t;
+typedef UINTN    uintptr_t;
+typedef UINTN    size_t;
+typedef BOOLEAN  bool;
+
+#define true   (1 == 1)
+#define false  (1 == 0)
+
+//
+// Definitions for global constants used by libfdt library routines
+//
+#define INT_MAX     0x7FFFFFFF           /* Maximum (signed) int value */
+#define INT32_MAX   0x7FFFFFFF           /* Maximum (signed) int32 value */
+#define UINT32_MAX  0xFFFFFFFF           /* Maximum unsigned int32 value */
+
+//
+// Function prototypes of libfdt Library routines
+//
+void *
+memset     (
+  void *,
+  int,
+  size_t
+  );
+
+int
+memcmp      (
+  const void *,
+  const void *,
+  size_t
+  );
+
+int
+strcmp      (
+  const char *,
+  const char *
+  );
+
+char *
+strchr     (
+  const char *,
+  int
+  );
+
+char *
+strrchr    (
+  const char *,
+  int
+  );
+
+unsigned long
+strtoul     (
+  const char *,
+  char **,
+  int
+  );
+
+char *
+strcpy (
+  char        *strDest,
+  const char  *strSource
+  );
+
+//
+// Macros that directly map functions to BaseLib, BaseMemoryLib, and DebugLib functions
+//
+#define memcpy(dest, source, count)         CopyMem(dest,source, (UINTN)(count))
+#define memset(dest, ch, count)             SetMem(dest, (UINTN)(count),(UINT8)(ch))
+#define memchr(buf, ch, count)              ScanMem8(buf, (UINTN)(count),(UINT8)ch)
+#define memcmp(buf1, buf2, count)           (int)(CompareMem(buf1, buf2, (UINTN)(count)))
+#define memmove(dest, source, count)        CopyMem(dest, source, (UINTN)(count))
+#define strlen(str)                         (size_t)(AsciiStrLen(str))
+#define strnlen(str, count)                 (size_t)(AsciiStrnLenS(str, count))
+#define strncpy(strDest, strSource, count)  AsciiStrnCpyS(strDest, MAX_STRING_SIZE, strSource, (UINTN)count)
+#define strcat(strDest, strSource)          AsciiStrCatS(strDest, MAX_STRING_SIZE, strSource)
+#define strcmp(string1, string2, count)     (int)(AsciiStrCmp(string1, string2))
+#define strncmp(string1, string2, count)    (int)(AsciiStrnCmp(string1, string2, (UINTN)(count)))
+
+#endif /* FDT_LIB_SUPPORT_H_ */