fscrypt: move fscrypt_has_encryption_key() to supp/notsupp headers

fscrypt_has_encryption_key() is already split into two versions
depending on whether the filesystem is being built with encryption
support or not.  Move them into the appropriate headers.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

include/linux/fscrypt_supp.h

@@ -11,6 +11,11 @@
 #ifndef _LINUX_FSCRYPT_SUPP_H
 #define _LINUX_FSCRYPT_SUPP_H
 
+static inline bool fscrypt_has_encryption_key(const struct inode *inode)
+{
+	return (inode->i_crypt_info != NULL);
+}
+
 /* crypto.c */
 extern struct kmem_cache *fscrypt_info_cachep;
 extern struct fscrypt_ctx *fscrypt_get_ctx(const struct inode *, gfp_t);