win32*.sh: move debug symbols to separate files

win32*.sh: move debug symbols to separate files

This patch simplifies releasing Windows binaries along with debug
symbols.

By default, we're going to provide minimum debug information (-g1).
The symbols are extracted from the binaries and placed in separate
files in the ".debug" folder, which is used by gdb implicitly.

This is more convenient than having separate versions of the binaries,
with or without debug symbols.

Signed-off-by: Lucian Petrut <lpetrut@cloudbasesolutions.com>