debug: do not force installation of gdbserver

The BR2_ENABLE_DEBUG option selects the compilation and installation
of gdbserver on the target. This is a bit restrictive, especially for
external toolchains, which may already contain a gdbserver on the
target.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>

Config.in

@@ -205,7 +205,6 @@ config BR2_DEPRECATED
 
 config BR2_ENABLE_DEBUG
 	bool "build packages with debugging symbols"
-	select BR2_PACKAGE_GDB_SERVER
 	help
 	  Build packages with debugging symbols
 	  enabled