configs: phycore_am62x_a53_defconfig: Merge am62x_a53_usbdfu.config

Merge the am62x_a53_usbdfu.config into the phyCORE-AM62x A53 defconfig to
properly support USB DFU boot.

This config was made with the following command:

    make ARCH=arm CROSS_COMPILE=aarch64-linux-gnu- \
        phycore_am62x_a53_defconfig am62x_a53_usbdfu.config

However, CONFIG_USB_GADGET_MANUFACTURER was not merged to keep Phytec
as manufacturer.

Signed-off-by: Daniel Schultz <d.schultz@phytec.de>
diff --git a/configs/phycore_am62x_a53_defconfig b/configs/phycore_am62x_a53_defconfig
index 7bbd801..07a1fff 100644
--- a/configs/phycore_am62x_a53_defconfig
+++ b/configs/phycore_am62x_a53_defconfig
@@ -92,7 +92,7 @@
 CONFIG_CLK_TI_SCI=y
 CONFIG_DFU_MMC=y
 CONFIG_DFU_RAM=y
-CONFIG_SYS_DFU_DATA_BUF_SIZE=0x5000
+CONFIG_SYS_DFU_DATA_BUF_SIZE=0x40000
 CONFIG_SYS_DFU_MAX_FILE_SIZE=0x800000
 CONFIG_DMA_CHANNELS=y
 CONFIG_TI_K3_NAVSS_UDMA=y