PCI: qcom-ep: Remove surplus dev_err() when using platform_get_irq_byname()

PCI: qcom-ep: Remove surplus dev_err() when using platform_get_irq_byname()

There is no need to call the dev_err() function directly to print a
custom message when handling an error from either the platform_get_irq()
or platform_get_irq_byname() functions as both are going to display an
appropriate error message in case of a failure.

This change is as per suggestions from Coccinelle, e.g.,
  drivers/pci/controller/dwc/pcie-qcom-ep.c:556:2-9: line 556 is redundant because platform_get_irq() already prints an error

Related:
  https://lore.kernel.org/all/20210310131913.2802385-1-kw@linux.com/
  https://lore.kernel.org/all/20200802142601.1635926-1-kw@linux.com/

Link: https://lore.kernel.org/r/20211027112931.37182-1-kw@linux.com
Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>