RFR: 8253219: Epsilon: clean up unnecessary includes

[Thomas Schatzl]

Hi,

On 16.09.20 09:49, Aleksey Shipilev wrote:
> Static analysis shows a few #include statements in gc/epsilon that are not needed.
> 
> Testing: Linux x86_64 {release, fastdebug, slowdebug} x {+PCH, -PCH}
> 

- in epsilonMonitoringSupport.cpp, the include for allocation.inline.hpp 
is correct, CHeapObj is declared there.
The allocation.hpp one is superfluous though.

Looks good otherwise. I do not need a re-review for this change.

Thomas