[PATCH V3] drm/ast: Fixed CVE for DP501

[Bug][DP501] If ASPEED P2A (PCI to AHB) bridge is disabled and disallowed for CVE_2019_6260 item3, and then the monitor's EDID is unable read through Parade DP501. The reason is the DP501's FW is mapped to BMC addressing space rather than Host addressing space. The resolution is that using "pci_iom

[PATCH V3] drm/ast: Fixed CVE for DP501

[Bug][DP501] If ASPEED P2A (PCI to AHB) bridge is disabled and disallowed for CVE_2019_6260 item3, and then the monitor's EDID is unable read through Parade DP501. The reason is the DP501's FW is mapped to BMC addressing space rather than Host addressing space. The resolution is that using "pci_iom