MS-DOS and Turbo Pascal are a way different from Free Pascal and linux. I've seen zillions of posts like this one degenerating in a flame about executables size, dependencies, rtl, cross compiling, and so on
In order to avoid it, take a deep breath and read this.

However, a way to obtain a bare bone executable as you want is to rewrite the rtl, stripping down all the stuff you don't need.
Another way is the one I used in the first steps of fpc4gba: call the compiler with -s (don't call assembler and linker), edit by hand the .s file cutting all RTL references, assemble and link it.