samples: drivers: can: increase the maximum number of shell arguments
samples: drivers: can: increase the maximum number of shell arguments

Remove the custom Kconfig value for CONFIG_SHELL_ARGC_MAX as it is too low
to account for the new arguments to the "can send" shell command.

The default for CONFIG_SHELL_ARGC_MAX was increased to 20 in
32ebeb0a5c841b2f93563b7cd4c626fc51eda84f which is sufficient for sending
non-CAN-FD format frames using the new "can send" shell command.

Signed-off-by: Henrik Brix Andersen <24a3f13c22635bab658e39fc5f1e63c575328aae@vestas.com>

galak/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr,finikorg/zephyr,galak/zephyr,zephyrproject-rtos/zephyr,galak/zephyr,zephyrproject-rtos/zephyr,finikorg/zephyr,galak/zephyr,finikorg/zephyr,finikorg/zephyr,zephyrproject-rtos/zephyr,galak/zephyr,finikorg/zephyr