Renaming libtool* to glibtool* might require root permission.

Define DO_MV as "mv" or "sudo mv", depending on whether the user has
write access to /usr/local/bin, and use it to rename libtool* to
glibtool* and vice versa.

Change-Id: Ifbef4daa4521852bc200522743df9d23e7f0d1c2
Reviewed-on: https://code.wireshark.org/review/4295
Reviewed-by: Guy Harris <guy@alum.mit.edu>