Make Makefile less location-dependent, port to fixed SDK 0.9.3, use flashi instead of esptool simplifying build

Hi,
so here is a bunch of changes that were stacking up over here.
* The first commit (9357a82) is fixing the Makefile to be less position-depentdent by just asking the binutils for paths.
* The second commit adds a few headers for the drivers that were needed for building (I might try to remove these again in the future).
* The third commit (6fdaea6) includes fixes to build against the fixed version of espressif's SDK version 0.9.3 that can be found here: https://github.com/jaseg/espressif-esp8266-sdk . The main change there is the removal of the non-standard integer typedefs previously found in c_types.h.
* The fourth commit modifies the esp8266 makefile to just output an elf file that can later directly be passed to my modified version of upstream esptool.py and esptool-ck, dubbed flashi (since there are already enough esptools on this planet): https://github.com/jaseg/flashi


BTW, I successfully built this firmware against https://github.com/tommie/lx106-hal .

Best regards,
jaseg