[🍒 5.10] CMake: ensure Swift host tools depend on HostCompatibilityLibs target
At the time I implemented #60728, I did not realize that in all the
bootstrapping mode we need to depend on the compatibility libraries we
build -- otherwise when targeting a low deployment target we risk
failing because we are not able to find such libraries.
Addresses rdar://126552386
(cherry picked from commit 4d14497016780add0b674f68a7ed4594ac8ce3a9)