In commit 998a4f589d, all but one return
statement was updated to return the error proper value. This commit
rectifies that missed return statement.
libctf/
ctf-types.c (ctf_type_resolve_unsliced): Return CTF_ERR on error.
Signed-off-by: Torbjörn SVENSSON <torbjorn.svensson@foss.st.com>