To compile for systems without much space (floppy distributions etc), you can create a single binary. This will save disk space by avoiding repeated code between the various parts. If you are familiar with BusyBox, it's the same principle.
To compile the multi-binary, first make clean
(if you've compiled previously), then
make PROGRAMS="programs you want here" MULTI=1
To use the binary, symlink it from the desired executable:
ln -s dropbearmulti dropbear
ln -s dropbearmulti dbclient
etc.
Then execute as normal:
./dropbear <options here>