[sqlite] new cross-compiling logic - how do I set build/target copmilers?

[Makavy, Erez (Erez)]

I'm trying to cross-compile sqlite 3.4.0,
and I see that the cross-compile  logic (in configure)  was changed
since 3.3.14 .
 
Previously I used the environment variable config_BUILD_CC and
config_TARGET_CC to set the build/target compilers.
 
How do I now set the build/target compilers?
 
Thanks,
Erez.