Adding gdbserver compiled with Android toolchain

gdbserver needs to be linked with the bionic libraries
for proper multi-threaded debugging. Without the proper
knowledge on bionic's pthread implementation, gdbserver
will crash when trying to break at an address not on the
main thread of a process.

gdb source found at: git://android.git.kernel.org/toolchain/gdb.git
branch: master
commit: 3954a66c7a69

gdb version: gdb-7.1.x (same as gdb found in arm-eabi-4.4.3 prebuilts)
toolchain: arm-eabi-4.4.3

Change-Id: Ic5e1fa112f1e7f104e0d9a012c634035e09573d4