posix: deprecated: remove new options without deprecation A few previously deprecated Kconfig options have not yet been present for 1 release cycle and can (theoretically) just be removed, without deprecation (see next commit). * GETENTROPY * POSIX_CONFSTR * POSIX_ENV * POSIX_SYSLOG For dependency information, please see https://docs.zephyrproject.org/3.6.0/kconfig.html#kconfig-search Signed-off-by: Chris Friedt <cfriedt@tenstorrent.com>