Fix sbrk.S to use _end symbol the same way brk.s was fixed some time ago. sbrk.S should have gotten the same change then but was forgotten.
Fix sbrk.S to use _end symbol the same way brk.s was fixed some time
ago. sbrk.S should have gotten the same change then but was forgotten.

Approved by:	re (bmah)
PR:		kern/114049

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase