RFR: 8204477: Count linkage errors and print in Exceptions::print_exception_counts_on_error

[René Schünemann]

Hi,

can I please get a review for the following change:

Bug: https://bugs.openjdk.java.net/browse/JDK-8204477
Webrev: http://cr.openjdk.java.net/~goetz/wr18/rene/webrev_8204477/01/

This change counts linkage errors and prints the number of linkage
errors thrown in the Exceptions::print_exception_counts_on_error,
which is used when writing the hs_error file.

Thank you,
Rene