build-infra: clean up typos

These are from emails sent to the build lists. Collected here so they don't get lost:

1) checking headful support... inlude support for both headful and headless

2) in NewMakefile.gmk
# Run the makefile with an arbitraty SPEC

3) in common/makefiles/JavaCompilation.gmk

 line 162: dechipher.

 line 518: buliding