kbuild: Use Elfnn_Half as replacement for Elfnn_Section

The Elfnn_Section is not available on all platforms,
noteworthy are cygwin.
Use the safe replacement _Half.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>

scripts/mod/modpost.h

@@ -17,7 +17,7 @@
 #define Elf_Shdr    Elf32_Shdr
 #define Elf_Sym     Elf32_Sym
 #define Elf_Addr    Elf32_Addr
-#define Elf_Section Elf32_Section
+#define Elf_Section Elf32_Half
 #define ELF_ST_BIND ELF32_ST_BIND
 #define ELF_ST_TYPE ELF32_ST_TYPE
 
@@ -31,7 +31,7 @@
 #define Elf_Shdr    Elf64_Shdr
 #define Elf_Sym     Elf64_Sym
 #define Elf_Addr    Elf64_Addr
-#define Elf_Section Elf64_Section
+#define Elf_Section Elf64_Half
 #define ELF_ST_BIND ELF64_ST_BIND
 #define ELF_ST_TYPE ELF64_ST_TYPE