net: sockets: Make NET_SOCKETS_POSIX_NAMES be on by default
net: sockets: Make NET_SOCKETS_POSIX_NAMES be on by default

Zephyr socket subsystem has come a long way since initial experimental
alternative to internal Zephyr networking API. Its configuration also
mirrors the usual conservative approach, where a user needs to
explicitly enable options to get "more" features. And as an
experimental API, socket subsystem was initially developed as
namespaced API, where all functions/structures are prefixed with
"zsock_", and to get standard names, CONFIG_NET_SOCKETS_POSIX_NAMES
needs to be set (or alternatively, CONFIG_POSIX_API needs to be, which
enabled full POSIX subsys overall).

However, a few years later, sockets are the standard networking API,
and in majority of cases its used under the standard POSIX names.
Necessity to explicitly set an option to achieve this effects, and
confusion which results from it - are just unneeded chores for users.

So, switch CONFIG_NET_SOCKETS_POSIX_NAMES to be on by default (unless
CONFIG_POSIX_API is already defined). It still can be explicitly
disabled if needed (but usecases for that would be peculiar and rare).

Addresses #34165

Signed-off-by: Paul Sokolovsky <35cb557f011771c94f127d6fef99f804b62203f5@linaro.org>

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