PCI: dwc: Move MSI interrupt setup into DWC common code

PCI: dwc: Move MSI interrupt setup into DWC common code

Platforms using the built-in DWC MSI controller all have a dedicated
interrupt with "msi" name or at index 0, so let's move setting up the
interrupt to the common DWC code.

spear13xx and dra7xx are the 2 oddballs with muxed interrupts, so
we need to prevent configuring the MSI interrupt by setting msi_irq
to negative.

Link: https://lore.kernel.org/r/20201105211159.1814485-9-robh@kernel.org
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Jingoo Han <jingoohan1@gmail.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Kukjin Kim <kgene@kernel.org>
Cc: Krzysztof Kozlowski <krzk@kernel.org>
Cc: Richard Zhu <hongxing.zhu@nxp.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Pengutronix Kernel Team <kernel@pengutronix.de>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: NXP Linux Team <linux-imx@nxp.com>
Cc: Yue Wang <yue.wang@Amlogic.com>
Cc: Kevin Hilman <khilman@baylibre.com>
Cc: Neil Armstrong <narmstrong@baylibre.com>
Cc: Jerome Brunet <jbrunet@baylibre.com>
Cc: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
Cc: Xiaowei Song <songxiaowei@hisilicon.com>
Cc: Binghui Wang <wangbinghui@hisilicon.com>
Cc: Stanimir Varbanov <svarbanov@mm-sol.com>
Cc: Andy Gross <agross@kernel.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Pratyush Anand <pratyush.anand@gmail.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Jonathan Hunter <jonathanh@nvidia.com>
Cc: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: linux-samsung-soc@vger.kernel.org
Cc: linux-amlogic@lists.infradead.org
Cc: linux-arm-kernel@axis.com
Cc: linux-arm-msm@vger.kernel.org
Cc: linux-tegra@vger.kernel.org