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/builtin.c

@@ -51,13 +51,9 @@
 #include <nuttx/fs/fs.h>
 #include <nuttx/fs/ioctl.h>
 #include <nuttx/binfmt/binfmt.h>
-#include <nuttx/binfmt/builtin.h>
+#include <nuttx/lib/builtin.h>
 
-#ifdef CONFIG_BUILTIN
-
-/****************************************************************************
- * Pre-processor Definitions
- ****************************************************************************/
+#ifdef HAVE_BUILTIN_CONTEXT
 
 /****************************************************************************
  * Private Function Prototypes
@@ -197,5 +193,5 @@ void builtin_uninitialize(void)
   (void)unregister_binfmt(&g_builtin_binfmt);
 }
 
-#endif /* CONFIG_BUILTIN */
+#endif /* HAVE_BUILTIN_CONTEXT */