PCI: dwc: artpec6: Remove unused defines

Commit b015b37e ("PCI: artpec6: Stop enabling writes to
DBI read-only registers") removed the only write using these
defines, but it did not remove the defines.
Remove the defines since they are now unused.
Signed-off-by: Niklas Cassel <niklas.cassel@axis.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>

drivers/pci/dwc/pcie-artpec6.c

@@ -37,9 +37,6 @@ struct artpec6_pcie {
 #define PCIE_PHY_DEBUG_R0		(PL_OFFSET + 0x28)
 #define PCIE_PHY_DEBUG_R1		(PL_OFFSET + 0x2c)
 
-#define MISC_CONTROL_1_OFF		(PL_OFFSET + 0x1bc)
-#define  DBI_RO_WR_EN			1
-
 /* ARTPEC-6 specific registers */
 #define PCIECFG				0x18
 #define  PCIECFG_DBG_OEN		(1 << 24)