nfc: st-nci: Fix typo when changing from st21nfcb to st-nci

Replace ST21NFCB with ST_NCI or st21nfcb with st_nci as it
was forgotten in commit "nfc: st-nci: Rename st21nfcb to st-nci"
ed06aeef

Cc: stable@vger.kernel.org
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>