linux-phytec-fsl

NFC: dts: st21nfca_i2c: Correct minor typo in documentation

Replaced st,st21nfca-i2c by st,st21nfca_i2c to be concistent
with below configuration and driver in drivers/nfc/st21nfca/

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