freeELF is not in e9tool namespace

[liangjs]

The freeELF function is not defined in the e9tool namespace.

e9patch/src/e9tool/e9frontend.cpp

Line 1448 in 855e8b8

 void freeELF(ELF *elf) 

This will cause plugins unable to call use this function.

undefined symbol: _ZN6e9tool7freeELFEPNS_3ELFE

[GJDuck]

Thanks for the report. It is fixed.