dt-bindings: spi: mxic: The interrupt property is not mandatory

stable inclusion
from stable-v5.10.110
commit 7704f243cbbd1393cc42f40abebf6810bfc70f1b
bugzilla: https://gitee.com/openeuler/kernel/issues/I574AL

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=7704f243cbbd1393cc42f40abebf6810bfc70f1b

--------------------------------

commit 90c204d3 upstream.

The interrupt property is not mandatory at all, this property should not
be part of the required properties list, so move it into the optional
properties list.

Fixes: 326e5c8d ("dt-binding: spi: Document Macronix controller bindings")
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: NRob Herring <robh@kernel.org>
Reviewed-by: NMark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/linux-mtd/20211216111654.238086-8-miquel.raynal@bootlin.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NYu Liao <liaoyu15@huawei.com>
Reviewed-by: NWei Li <liwei391@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

Documentation/devicetree/bindings/spi/spi-mxic.txt

@@ -8,11 +8,13 @@ Required properties:
 - reg: should contain 2 entries, one for the registers and one for the direct
        mapping area
 - reg-names: should contain "regs" and "dirmap"
-- interrupts: interrupt line connected to the SPI controller
 - clock-names: should contain "ps_clk", "send_clk" and "send_dly_clk"
 - clocks: should contain 3 entries for the "ps_clk", "send_clk" and
 	  "send_dly_clk" clocks
 
+Optional properties:
+- interrupts: interrupt line connected to the SPI controller
+
 Example:
 
 	spi@43c30000 {