Convert CONFIG_SYS_PBSIZE to Kconfig

This converts the following to Kconfig:
   CONFIG_SYS_PBSIZE

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/s5p_goni_defconfig b/configs/s5p_goni_defconfig
index 5c39c1d..2b4cb5c 100644
--- a/configs/s5p_goni_defconfig
+++ b/configs/s5p_goni_defconfig
@@ -21,6 +21,7 @@
 CONFIG_HUSH_PARSER=y
 # CONFIG_AUTO_COMPLETE is not set
 CONFIG_SYS_PROMPT="Goni # "
+CONFIG_SYS_PBSIZE=384
 # CONFIG_CMD_XIMG is not set
 CONFIG_CMD_THOR_DOWNLOAD=y
 CONFIG_CMD_DFU=y