Replace mail address with the URL in copyright header

Replace mail address with the URL in copyright header

The copyright header in most of GDB files were changed from mail address
to the URL in the conversion to GPLv3 in Aug 2007.  However, some files
still use mail address instead of the URL.  This patch fixes them.

gdb/testsuite:

2017-12-01  Yao Qi  <yao.qi@linaro.org>

	* gdb.arch/aarch64-atomic-inst.exp: Replace mail address with
	the URL in copyright header.
	* gdb.arch/aarch64-fp.exp: Likewise.
	* gdb.arch/ppc64-atomic-inst.exp: Likewise.
	* gdb.arch/ppc64-isa207-atomic-inst.exp: Likewise.
	* gdb.base/expand-psymtabs.exp: Likewise.
	* gdb.cp/expand-psymtabs-cxx.exp: Likewise.
	* gdb.fortran/common-block.exp: Likewise.
	* gdb.fortran/common-block.f90: Likewise.
	* gdb.fortran/logical.exp: Likewise.
	* gdb.fortran/vla-datatypes.f90: Likewise.
	* gdb.fortran/vla-sub.f90: Likewise.