XFSQA 122 on machines with xfs_lazy_sb.patch have failed due to the addition of __be3...

XFSQA 122 on machines with xfs_lazy_sb.patch have failed due to the addition of __be32 agf_btreeblks to xfs_agf_t.

This change causes 122 detect whether the patch is installed by greping for lazy count in mkfs output, the xfs_agf_t size is then filtered based on the patch status.
The original intention was to check /lib/modules/$(uname -r)/source/fs/xfs/xfs_ag.h for btreeblks and filter on this, however the kernel source is not a prereq for XFSQA.
Merge of master-melb:xfs-cmds:28014a by kenmcd.

  pipe get_structs.c output through _type_size_filter to filter out known changes to xfs type sizes