REORG: ssl: move the ckch_store related functions to src/ssl_ckch.c

Move the cert_key_and_chain functions:

int ssl_sock_load_files_into_ckch(const char *path, struct cert_key_and_chain *ckch, char **err);
int ssl_sock_load_pem_into_ckch(const char *path, char *buf, struct cert_key_and_chain *ckch , char **err);
void ssl_sock_free_cert_key_and_chain_contents(struct cert_key_and_chain *ckch);

int ssl_sock_load_key_into_ckch(const char *path, char *buf, struct cert_key_and_chain *ckch , char **err);
int ssl_sock_load_ocsp_response_from_file(const char *ocsp_path, char *buf, struct cert_key_and_chain *ckch, char **err);
int ssl_sock_load_sctl_from_file(const char *sctl_path, char *buf, struct cert_key_and_chain *ckch, char **err);
int ssl_sock_load_issuer_file_into_ckch(const char *path, char *buf, struct cert_key_and_chain *ckch, char **err);

And the utility ckch_store functions:

void ckch_store_free(struct ckch_store *store)
struct ckch_store *ckch_store_new(const char *filename, int nmemb)
struct ckch_store *ckchs_dup(const struct ckch_store *src)
ckch_store *ckchs_lookup(char *path)
ckch_store *ckchs_load_cert_file(char *path, int multi, char **err)
diff --git a/include/types/ssl_ckch.h b/include/types/ssl_ckch.h
index 3a49b40..db59bb7 100644
--- a/include/types/ssl_ckch.h
+++ b/include/types/ssl_ckch.h
@@ -71,6 +71,10 @@
 	char path[0];
 };
 
+/* forward declarations for ckch_inst */
+struct ssl_bind_conf;
+struct crtlist_entry;
+
 /*
  * This structure describe a ckch instance. An instance is generated for each
  * bind_conf.  The instance contains a linked list of the sni ctx which uses