Improve compiler detection for x86_64 target

[galpeter]

Related issue: #71

JerryScript-DCO-1.0-Signed-off-by: Peter Gal [email protected]

[ruben-ayrapetyan]

@galpeter ,
The way to search for compiler is ok.
However, it seems that using strip if x86-64-[unknown-]-linux-gnu-strip is not found, could break cross compilation to x86_64, as the strip would probably refer to version for host architecture, not the target.

Please add "FIXME" comment to line for finding strip with the following content:
"# FIXME: This can break cross compilation to x86_64, when it would be supported".

Then merge the commit to master through rebasing, fast-forward merge and make push.

After that, please, raise an issue for the FIXME, sufficiently describing why the change is necessary,
how this can affect cross compilation, and reference to the commit.
If there are any ideas how the issue could be fixed, please add them also.

[galpeter]

@ruben-ayrapetyan
Would it be ok to reuse the #71 issue?

[egavrin]

@galpeter yes, it'd OK.