mx does not like .hotspot_compiler

[Eric Caspole]

We are usually running Graal with -server so only the HSAIL part is 
built with Graal. We were hitting an assert in C2 code and eventually I 
tried using a .hotspot_compiler file, but it makes mx fail, for example:


$ cat .hotspot_compiler
exclude java/lang/String indexOf


$ ./mx.sh  --vm server --vmbuild fastdebug  unittest -server -ea -esa 
-XX:-TraceGPUInteraction  -Dcom.amd.sumatra.offload.immediate=true 
hsail.test.lambda
Traceback (most recent call last):
   File "/home/ecaspole/views/graal-default/graal/mxtool/mx.py", line 
4912, in <module>
     main()
   File "/home/ecaspole/views/graal-default/graal/mxtool/mx.py", line 
4849, in main
     defaultJdk = JavaConfig(opts.java_home, opts.java_dbg_port)
   File "/home/ecaspole/views/graal-default/graal/mxtool/mx.py", line 
1740, in __init__
     assert output[1] == 'version'
AssertionError


Even a completely empty .hotspot_compiler file causes it to fail.
Eventually I found -XX:CompileCommand= worked OK.