fixincludes: FIx up for Debian/Ubuntu includes

As reported by Tobias, my C++ _Float{16,32,64,128,32x,64x,128x} support
patch broke Debian/Ubuntu bootstraps.  The problem is that there
glibc bits/floatn.h and bits/floatn-common.h isn't in /usr/include/
directly, but in a subdirectory like /usr/include/x86_64-linux-gnu/
Seems other fixinclude rules for bits/* headers use
files = bits/whatever.h, "*/bits/whatever.h";
so this patch just follows the suit.

2022-06-27  Jakub Jelinek  <jakub@redhat.com>

	* inclhack.def (glibc_cxx_floatn_1, glibc_cxx_floatn_2,
	glibc_cxx_floatn_3): Add to files also "*/bits/floatn.h"
	and "*/bits/floatn-common.h".
	* fixincl.x: Regenerated.