MAINTAINERS: rectify entries for ARM DRM DRIVERS after dt conversion

The three commits:

  36fd2a6 ("dt-bindings: display: convert Arm HDLCD to DT schema")
  0f69835 ("dt-bindings: display: convert Arm Komeda to DT schema")
  2c8b082 ("dt-bindings: display: convert Arm Mali-DP to DT schema")

convert the arm display dt-bindings, arm,*.txt to arm,*.yaml, but miss to
adjust its reference in MAINTAINERS.

Hence, ./scripts/get_maintainer.pl --self-test=patterns complains about
broken references.

Repair these file references in ARM HDLCD DRM DRIVER, ARM KOMEDA DRM-KMS
DRIVER and ARM MALI-DP DRM DRIVER.

Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Acked-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220601041746.22986-1-lukas.bulwahn@gmail.com

Author: bulwahn

MAINTAINERS

@@ -1507,7 +1507,7 @@ F:	drivers/clocksource/arm_arch_timer.c
 ARM HDLCD DRM DRIVER
 M:	Liviu Dudau <liviu.dudau@arm.com>
 S:	Supported
-F:	Documentation/devicetree/bindings/display/arm,hdlcd.txt
+F:	Documentation/devicetree/bindings/display/arm,hdlcd.yaml
 F:	drivers/gpu/drm/arm/hdlcd_*
 
 ARM INTEGRATOR, VERSATILE AND REALVIEW SUPPORT
@@ -1542,7 +1542,7 @@ M:	Mihail Atanassov <mihail.atanassov@arm.com>
 L:	Mali DP Maintainers <malidp@foss.arm.com>
 S:	Supported
 T:	git git://anongit.freedesktop.org/drm/drm-misc
-F:	Documentation/devicetree/bindings/display/arm,komeda.txt
+F:	Documentation/devicetree/bindings/display/arm,komeda.yaml
 F:	Documentation/gpu/komeda-kms.rst
 F:	drivers/gpu/drm/arm/display/include/
 F:	drivers/gpu/drm/arm/display/komeda/
@@ -1564,7 +1564,7 @@ M:	Brian Starkey <brian.starkey@arm.com>
 L:	Mali DP Maintainers <malidp@foss.arm.com>
 S:	Supported
 T:	git git://anongit.freedesktop.org/drm/drm-misc
-F:	Documentation/devicetree/bindings/display/arm,malidp.txt
+F:	Documentation/devicetree/bindings/display/arm,malidp.yaml
 F:	Documentation/gpu/afbc.rst
 F:	drivers/gpu/drm/arm/