cmake: FindBabbleSim: Ensure BSIM variables are available everywhere

Ensure the two BSIM variables BSIM_OUT_PATH and BSIM_COMPONENTS_PATH are
available everywhere also as a cmake variable as quite a few apps use
them. (Some apps try to get them as an environment var, some as a cmake
var).

When the user had them set in the environment, and the BabbleSim module
uses zephyr_get() to try to find them, this also sets them globally.
But otherwise, if we just deduced them in this module, we were only
setting them in the enviroment, so apps which expected them globally
would not build properly.

Signed-off-by: Alberto Escolar Piedras <alberto.escolar.piedras@nordicsemi.no>

Author: aescolar

cmake/modules/FindBabbleSim.cmake

@@ -60,9 +60,12 @@ if((NOT DEFINED BSIM_COMPONENTS_PATH) OR (NOT DEFINED BSIM_OUT_PATH))
   )
 endif()
 
-# Many apps cmake files (in and out of tree) expect these environment variables. Lets provide them:
+# Many apps cmake files (in and out of tree) expect these either as environment variables or preset
+# variables. Lets provide them in any case:
 set(ENV{BSIM_COMPONENTS_PATH} ${BSIM_COMPONENTS_PATH})
 set(ENV{BSIM_OUT_PATH} ${BSIM_OUT_PATH})
+set(BSIM_COMPONENTS_PATH ${BSIM_COMPONENTS_PATH} CACHE PATH "BabbleSim components folder")
+set(BSIM_OUT_PATH ${BSIM_OUT_PATH} CACHE PATH "BabbleSim build output folder")
 
 # Let's check that it is new enough and built,
 # so we provide better information to users than a compile error: