AArch64 build failures with static DR

#975 made static DR first-class-supported and it builds on its own and in small startstop test apps, but linking with drmemtrace it fails to link:

https://travis-ci.org/DynamoRIO/dynamorio/jobs/161201683

Linking CXX executable ../bin64/tool.drcacheoff.burst_static
../../lib64/debug/libdynamorio_static.a(libdynamorio_static.o): In function `check_param_bounds':
/home/travis/build/DynamoRIO/dynamorio/core/options.c:561:(.text+0x108c4): .relocation truncated to fit: R_AARCH64_LD64_GOT_LO12_NC against `main_logfile'
/home/travis/build/DynamoRIO/dynamorio/core/options.c:561:(.text+0x10934): relocation truncated to fit: R_AARCH64_LD64_GOT_LO12_NC against `main_logfile'
../../lib64/debug/libdynamorio_static.a(libdynamorio_static.o): In function `update_dynamic_options':
/home/travis/build/DynamoRIO/dynamorio/core/optionsx.h:221:(.text+0x339f8): relocation truncated to fit: R_AARCH64_LD64_GOT_LO12_NC against `main_logfile'
/home/travis/build/DynamoRIO/dynamorio/core/optionsx.h:227:(.text+0x33b28): relocation truncated to fit: R_AARCH64_LD64_GOT_LO12_NC against `main_logfile'
/home/travis/build/DynamoRIO/dynamorio/core/optionsx.h:228:(.text+0x33c58): relocation truncated to fit: R_AARCH64_LD64_GOT_LO12_NC against `main_logfile'
/home/travis/build/DynamoRIO/dynamorio/core/optionsx.h:229:(.text+0x33d88): relocation truncated to fit: R_AARCH64_LD64_GOT_LO12_NC against `main_logfile'
/home/travis/build/DynamoRIO/dynamorio/core/optionsx.h:230:(.text+0x3!3eb8): relocation truncated to fit: R_AARCH64_LD64_GOT_LO12_NC against `main_logfile'
/home/travis/build/DynamoRIO/dynamorio/core/optionsx.h:231:(.text+0x33fe8): relocation truncated to fit: R_AARCH64_LD64_GOT_LO12_NC against `main_logfile'
/home/travis/build/DynamoRIO/dynamorio/core/optionsx.h:232:(.text+0x34118): relocation truncated to fit: R_AARCH64_LD64_GOT_LO12_NC against `main_logfile'
/home/travis/build/DynamoRIO/dynamorio/core/optionsx.h:233:(.text+0x34248): relocation truncated to fit: R_AARCH64_LD64_GOT_LO12_NC against `main_logfile'
/home/travis/build/DynamoRIO/dynamorio/core/optionsx.h:234:(.text+0x34378): additional relocation overflows omitted from the output
collect2: error: ld returned 1 exit status
make[2]: *** [clients/bin64/tool.drcacheoff.burst_static] Error 1
make[1]: *** [clients/drcachesim/CMakeFiles/tool.drcacheoff.burst_static.dir/all] Error 2

We'll have to disable larger static tests for A64 until we understand what is going on.