Slirp: added sanity check for correctly packed networking structures.
Cygwin shortcut script: option -mno-cygwin is obsolete and -mno-ms-bitfields is
required for Bochs as of GCC version 4.7.


git-svn-id: svn://svn.code.sf.net/p/bochs/code/trunk@12243 6c8e4198-a580-4521-a02f-c9ae86df1db9