This detail got lost in my previous cleanup change 9b4a812.
Also add a comment explaining why the host side of the
simulator needs to be built in 64-bit (wxWidgets).
Change-Id: I2a867f7f80b43d53e73348b19f6ae834600295f9
The only OS-ARCH combo that would have benefited from it
is linux-x86, but it explicitly used separate configurations
for the HOST_ and TARGET_ side of things.
This makes is clear which files are related to the HOST_
configuration and which ones are related to the TARGET_
configuration, and expands $(combo_target) to the only
possible/reasonable value that it could have had in every
file.
This also cleans up the simulator, by moving it in a single
place in TARGET_linux_x86 (since the only part that's special
is to use HOST_ settings even when building TARGET_ modules).
Change-Id: I2420eeb8cfe539f5807ec99cb3177ffb9f2476d5
