This commit moves shared builtin information out of binfmt/libbuiltin and into libs/libc/builtin where it can be shared. This should permit builtin application in the PROTECTED build where binfmt/libbuiltin is not available in user space.

Squashed commit of the following:

    Correct some additional compile-related issues.

    Move  include/nuttx/binfmt/builtin.h to include/nuttx/lib/builtin.h.  Move apps/builtin/lib_builtin_forindex.c to libs/libc/builtin/lib_builtin_forindex.c.

    Move binfmt/libbuiltin to libs/libc/builtin.  There are calls made directly from apps/nshlib into this logic and hence, must be part of a library that can be shared between the OS and applications.

binfmt/binfmt_initialize.c

@@ -40,10 +40,10 @@
 #include <nuttx/config.h>
 
 #include <nuttx/binfmt/binfmt.h>
-#include <nuttx/binfmt/builtin.h>
 #include <nuttx/binfmt/elf.h>
 #include <nuttx/binfmt/pcode.h>
 #include <nuttx/binfmt/nxflat.h>
+#include <nuttx/lib/builtin.h>
 
 #ifndef CONFIG_BINFMT_DISABLE
 
@@ -63,7 +63,7 @@ void binfmt_initialize(void)
 {
   int ret;
 
-#ifdef CONFIG_FS_BINFS
+#if defined(CONFIG_FS_BINFS) && defined(HAVE_BUILTIN_CONTEXT)
   ret = builtin_initialize();
   if (ret < 0)
     {