Since Autoconf places some important feature flags only into the
configuration header, it is necessary to include it globally to
guarantee a consistent build.
Move the include flags for files in the source tree from
configure.ac to Makefile.am where they belong. Also use
AM_CPPFLAGS instead of CFLAGS/CXXFLAGS to make sure the
files in the build/source tree are always picked up first.
Also, remove the include/libsigrok sub-directory from the
search path, thereby making the <libsigrok/> prefix mandatory
when building libsigrok itself. This matches the convention
already imposed on users of the library.
All of these error conditions are checked via the unit tests.
Also, add the following missing entries (analog trigger types):
- SR_TRIGGER_RISING
- SR_TRIGGER_EDGE
Daniel Elstner
Soeren Apel
Uwe Hermann
Bert Vermeulen