[9] RFR: 8140649: imageFile should use delete[] with new[]

[Artem Smotrakov]

Hello,

Please review this small fix for jdk9/dev repo.

It updates imageFile.cpp to use delete[] operator together with new[]. 
It also adds a check to ImageLocation::set_data(u1*) method to prevent a 
possible null-dereference.

Bug: https://bugs.openjdk.java.net/browse/JDK-8140649
Webrev: 
http://cr.openjdk.java.net/~asmotrak/image_file_new_delete/webrev.01/

Artem