rtld: Initialize _dl_error_catch_tsd without FUNCDESC relocation

Make _dl_initial_error_catch_tsd hidden, such that we do not need a
FUNCDESC relocation when initializing _dl_error_catch_tsd.

	* ldso/ldso/dl-tls.c (_dl_initial_error_catch_tsd): Declare hidden.

Signed-off-by: Mickaël Guêné <mickael.guene@st.com>
Signed-off-by: Christophe Lyon <christophe.lyon@st.com>

ldso/ldso/dl-tls.c

@@ -957,6 +957,7 @@ _dl_add_to_slotinfo (struct link_map  *l)
 /* Taken from glibc/elf/rtld.c */
 static bool tls_init_tp_called;
 
+rtld_hidden_proto(_dl_initial_error_catch_tsd)
 /* _dl_error_catch_tsd points to this for the single-threaded case.
    It's reset by the thread library for multithreaded programs.  */
 void ** __attribute__ ((const))