envs are stuck after args which are now possibly unaligned, and used
from a non-aligned pointer in prepare_process_ranges_args_envs (env)
The memory immediately after args/envs is copied anyway with memcpy_long,
so make sure the bits are initialized and realign env correctly
Fixes: 70e52faf36 ("flatten_strings: do not return unused trailing bits")
Change-Id: Ic747e947d151c0eea65dec36bc9c888cf6e0c394