fetch_packages: Add 'autoreconf' ivocation for the Thrift package

Patches for the Thrift modify its Makefile.am and the configure script
has to be regenerated. If autoreconf is not relaunch it causes errors
if the versions of aclocal, autoconf or automake differs on the build host
differ from those used while creating the package.

Change-Id: I1924d07c90416707509f50eea096668ecc569ff6

Conflicts:
	fetch_packages.py