various changes to the boot scripts

various changes to the boot scripts

configs/boot/iscsi-client.rcS:
configs/boot/nfs-client-dbench.rcS:
    don't use the /proc/m5 stuff, use the m5 binary
configs/boot/nfs-client-nhfsstone.rcS:
    set up checkpoints
    change nhfsstone configuration
configs/boot/nfs-client.rcS:
    use more memory
configs/boot/nfs-server.rcS:
    change the writeback frequency
    load a larger simulated disk image.
    create more nfsd threads

--HG--
extra : convert_revision : 242dfd261d62782c06847d64b9f6aa06664a1ec9