efi_loader: Select bounce buffers for known-bad boards

We know for certain that we have 32bit DMA hardware, but 64bit addresses
on LS2085A and ZynqMP, so let's enable EFI bounce buffers for all defconfigs
on these SoCs.

Signed-off-by: Alexander Graf <agraf@suse.de>
diff --git a/configs/xilinx_zynqmp_ep_defconfig b/configs/xilinx_zynqmp_ep_defconfig
index 37b8052..f342ed2 100644
--- a/configs/xilinx_zynqmp_ep_defconfig
+++ b/configs/xilinx_zynqmp_ep_defconfig
@@ -64,3 +64,4 @@
 CONFIG_G_DNL_VENDOR_NUM=0x03fd
 CONFIG_G_DNL_PRODUCT_NUM=0x0300
 # CONFIG_REGEX is not set
+CONFIG_EFI_LOADER_BOUNCE_BUFFER=y