samples: cellular: modem_shell: Cleanup configuration

Removed CONFIG_NRF_MODEM_LIB_TRACE from prj.conf because
snippet should be used to enable modem UART traces instead.

Signed-off-by: Tommi Kangas <[email protected]>

Author: tokangas

samples/cellular/modem_shell/prj.conf

@@ -78,8 +78,6 @@ CONFIG_NRF_MODEM_LIB=y
 CONFIG_NRF_MODEM_LIB_SHMEM_TX_SIZE=22528
 CONFIG_NRF_MODEM_LIB_SHMEM_RX_SIZE=8192
 CONFIG_NRF_MODEM_LIB_ON_FAULT_APPLICATION_SPECIFIC=y
-# Enable modem UART traces
-CONFIG_NRF_MODEM_LIB_TRACE=n
 
 # AT monitor library
 CONFIG_AT_MONITOR=y