kernel: disable CONFIG_PCIE_BUS_PERFORMANCE

The option was added in 5.9 and for some reason, it is causing performance
issues at least on an APU2 board with the igb device.
Switch CONFIG_PCIE_BUS_DEFAULT to fix the performance issues and match the
older kernel's behavior

Signed-off-by: Felix Fietkau <nbd@nbd.name>

target/linux/generic/config-5.10

@@ -4299,9 +4299,9 @@ CONFIG_PARTITION_ADVANCED=y
 # CONFIG_PCIE_AL is not set
 # CONFIG_PCIE_ALTERA is not set
 # CONFIG_PCIE_ARMADA_8K is not set
-# CONFIG_PCIE_BUS_DEFAULT is not set
+CONFIG_PCIE_BUS_DEFAULT=y
 # CONFIG_PCIE_BUS_PEER2PEER is not set
-CONFIG_PCIE_BUS_PERFORMANCE=y
+# CONFIG_PCIE_BUS_PERFORMANCE is not set
 # CONFIG_PCIE_BUS_SAFE is not set
 # CONFIG_PCIE_BUS_TUNE_OFF is not set
 # CONFIG_PCIE_BW is not set