Add sort_bss_symbols_by_size property for shared libs

If sort_bss_symbols_by_size is true, a shared library is built twice.
The first build generates an unsorted output file, which is used to
generate the symbol ordering file.  The output of the second build is
a shared library with its bss symbols sorted by their size.

With this, the only user of symbol_ordering_file, libc, is migrated to
use the new property, so we remove symbol_ordering_file support as well.

Bug: 135754984
Test: Build and check the resulting libc.so has its bss symbols sorted.
Change-Id: I5c892b44d82eb99cbc070cfa2c680be3087f3364