[Bug][Hexagon]Enabling gtest on Hexagon breaks skel library

[mehrdadh]

Running hexagon launcher on HDK boards shows this error after enabling gtest:

[08500/02]  34:12.022  7567:e85: CDSP: remote_handle_open: opened handle 0x0 for apps_remotectl  0123  listener_hexagon.c
[08500/02]  34:12.022  7564:e85: CDSP: remote_handle_open: opened handle 0x0 for apps_remotectl  0123  listener_hexagon.c
[08500/02]  34:12.023  7567:e85: CDSP: remote_handle_open: opened handle 0x39267d48 for apps_mem  0123  listener_hexagon.c
[08500/02]  34:12.025  7564:e85: CDSP: remote_handle_open: opened handle 0x39267e48 for apps_std  0123  listener_hexagon.c
[08500/02]  34:12.025  7567:e85: CDSP: fastrpc_uthread_create done for tidQ 0x7563, tidA 9876 (/frpc/f05ebcb0 tvm_rpc_android), stack 0x20100010 (size 262144), prio 192  0715  fastrpc_uprocess.c
[08500/02]  34:12.027  7567:e85: CDSP: fastrpc_uthread_create done for tidQ 0x7562, tidA 9884 (/frpc/f05ebcb0 tvm_rpc_android), stack 0x20140020 (size 262144), prio 192  0715  fastrpc_uprocess.c
[08500/03]  34:12.072  7564:e85: CDSP: undefined symbol PLT  #1380 pthread_key_delete in ./libhexagon_rpc_skel.so  0350  symbol.c
[08500/03]  34:12.073  7564:e85: CDSP: plt object relocation failure  0274  mdreloc.c
[08500/03]  34:12.073  7564:e85: CDSP: Error: dlopen_ex failed for libhexagon_rpc_skel.so (flags 258)  0862  rtld.c

cc @adstraw