[PARISC] Add NOTES section

Bisected bizarre kernel-space nullptr dereference in udev to commit
18991197b4b588255ccabf472ebc84db7b66a19c, adding the NOTES section fixes
it.

Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>

arch/parisc/kernel/vmlinux.lds.S

@@ -81,6 +81,8 @@ SECTIONS
   __ex_table : { *(__ex_table) }
   __stop___ex_table = .;
 
+  NOTES
+
   __start___unwind = .;         /* unwind info */
   .PARISC.unwind : { *(.PARISC.unwind) }
   __stop___unwind = .;