net: convert TFTP_TSIZE to proper Kconfig option

TFTP transfer size can be used to re-size the TFTP progress bar on
single line based on the server reported file size. The support for
this has been around from 2019, but it was never converted to proper
Kconfig.

While adding this new Kconfig, enable it by default for OMAP2+ and K3
devices also.

Signed-off-by: Tero Kristo <kristo@kernel.org>
diff --git a/configs/octeontx_83xx_defconfig b/configs/octeontx_83xx_defconfig
index 07c0d3f..a82c405 100644
--- a/configs/octeontx_83xx_defconfig
+++ b/configs/octeontx_83xx_defconfig
@@ -72,6 +72,7 @@
 CONFIG_ENV_SPI_MODE=0x0
 CONFIG_VERSION_VARIABLE=y
 CONFIG_NET_RANDOM_ETHADDR=y
+CONFIG_TFTP_TSIZE=y
 CONFIG_SCSI_AHCI=y
 CONFIG_AHCI_PCI=y
 CONFIG_DM_I2C=y