NFC: st21nfcb: Fix st21nfcb_nci_close

When closing st21nfcb driver, flag ST21NFCB_NCI_RUNNING can be cleared
only once the ndlc and the transport (i2c or spi) layers are released.

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