Remove gBn/sConstructorMap from headers.

Prebuilts that include toBinder() should no longer
link to gBnConstructorMap after rebuild.

After prebuilts are updated, symbols (in Static.cpp and
HidlPassthroughSupport.cpp) can be removed as well.

Test: walleye boots
Test: HAL def libs that link to libhidltransport no longer
      links to gBnConstructorMap / gBsConstructorMap.

Bug: 69122224
Change-Id: I6554a98a3068f9595666b7131df310e200551e45
4 files changed