The cmakev2 kconfig module sets sdkconfig output paths using internal
property names (__SDKCONFIG_HEADER, __SDKCONFIG_CMAKE, etc.), but
components like ULP read the public names (SDKCONFIG_HEADER,
SDKCONFIG_CMAKE). This results in empty values being passed to the ULP
sub-project, causing its CMake configure step to fail.
Add public aliases matching the cmake v1 property names for backward
compatibility.
Signed-off-by: Frantisek Hrbata <frantisek.hrbata@espressif.com>