* NEWS: Add "set sysroot" and "show sysroot".

	* NEWS: Add "set sysroot" and "show sysroot".
	* solib.c (solib_absolute_prefix): Delete.  Replace
	all uses with gdb_sysroot.
	(_initialize_solib): Add "set sysroot" and "show sysroot".
	Make "solib-absolute-prefix" an alias to it.

	* gdb.texinfo (Commands to specify files): Describe
	"set sysroot" and "show sysroot".
	(Using the `gdbserver' program): Lowercase argument
	to @var.  Expand description of setting up GDB on the
	host.