NFC: st21nfca: Synchronize i2c Tx and Rx path
NFC: st21nfca: Synchronize i2c Tx and Rx path

Stabilize communication by using a mutex.
This avoids running a write transaction during a read retry or a read
transaction during a write retry.

Signed-off-by: Christophe Ricard <7fc2cd33e78f60c767c0b054f476a876f109b675@st.com>
Signed-off-by: Samuel Ortiz <0ba86cb3f08bbb861958e54bd3438887adb4263c@linux.intel.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs