Require GNU make 3.82

Require GNU make 3.82

Gdbserver has failed to build with GNU make 3.81 since commit 08f10e02be.

Update the NEWS file to state that versions earlier than 3.82 are not
supported.

3.82 was released in 2010, 3.81 was released 2006. A quick investigation
of the default GNU make version provided across various distros found the
earliest provided version to be 3.82:
*RHEL 7, Centos 6 - make 3.82
*Fedora 27 - make 4.2.1
*OpenSuse 42.2, SLES11 - make 4.2.1
*Ubuntu 16.04/18.04 - make 4.1
*Debian Jessie - make 4.0

Note that Glibc requires at least 4.0, whereas GCC still allows 3.81.

gdb/ChangeLog:

	* NEWS: Require GNU make 3.82.