PCI: Rename PCI_IRQ_LEGACY to PCI_IRQ_INTX

Rename PCI_IRQ_LEGACY to PCI_IRQ_INTX to be more explicit about the type
of IRQ being referenced as well as to match the PCI specifications
terms. Redefine PCI_IRQ_LEGACY as an alias to PCI_IRQ_INTX to avoid the
need for doing the renaming tree-wide. New drivers and new code should
now prefer using PCI_IRQ_INTX instead of PCI_IRQ_LEGACY.

Link: https://lore.kernel.org/r/20231122060406.14695-2-dlemoal@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Reviewed-by: Serge Semin <fancer.lancer@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

Author: bjorn-helgaas

include/linux/pci.h

@@ -1073,11 +1073,13 @@ enum {
 	PCI_SCAN_ALL_PCIE_DEVS	= 0x00000040,	/* Scan all, not just dev 0 */
 };
 
-#define PCI_IRQ_LEGACY		(1 << 0) /* Allow legacy interrupts */
+#define PCI_IRQ_INTX		(1 << 0) /* Allow INTx interrupts */
 #define PCI_IRQ_MSI		(1 << 1) /* Allow MSI interrupts */
 #define PCI_IRQ_MSIX		(1 << 2) /* Allow MSI-X interrupts */
 #define PCI_IRQ_AFFINITY	(1 << 3) /* Auto-assign affinity */
 
+#define PCI_IRQ_LEGACY		PCI_IRQ_INTX /* Deprecated! Use PCI_IRQ_INTX */
+
 /* These external functions are only available when PCI support is enabled */
 #ifdef CONFIG_PCI