docs: dt: update writing-schema.rst references

Changeset b83db5b8 ("docs: dt: Group DT docs into relevant sub-sections")
renamed: Documentation/devicetree/writing-schema.rst
to: Documentation/devicetree/bindings/writing-schema.rst.

Update the cross-references accordingly.

Fixes: b83db5b8 ("docs: dt: Group DT docs into relevant sub-sections")
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/7cfddf303f1508d26f90d87546d3812faebfc5ba.1617279356.git.mchehab+huawei@kernel.orgSigned-off-by: Rob Herring <robh@kernel.org>

Documentation/devicetree/bindings/submitting-patches.rst

@@ -25,7 +25,7 @@ I. For patch submitters
 
        make dt_binding_check
 
-     See Documentation/devicetree/writing-schema.rst for more details about
+     See Documentation/devicetree/bindings/writing-schema.rst for more details about
      schema and tools setup.
 
   3) DT binding files should be dual licensed. The preferred license tag is

scripts/checkpatch.pl

@@ -3152,7 +3152,7 @@ sub process {
 		    ($line =~ /^new file mode\s*\d+\s*$/) &&
 		    ($realfile =~ m@^Documentation/devicetree/bindings/.*\.txt$@)) {
 			WARN("DT_SCHEMA_BINDING_PATCH",
-			     "DT bindings should be in DT schema format. See: Documentation/devicetree/writing-schema.rst\n");
+			     "DT bindings should be in DT schema format. See: Documentation/devicetree/bindings/writing-schema.rst\n");
 		}
 
 # Check for wrappage within a valid hunk of the file