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/aristainetos2ccslb_defconfig b/configs/aristainetos2ccslb_defconfig
index 4745f03..6bc78b7 100644
--- a/configs/aristainetos2ccslb_defconfig
+++ b/configs/aristainetos2ccslb_defconfig
@@ -24,6 +24,7 @@
 CONFIG_BOARD_EARLY_INIT_F=y
 CONFIG_HUSH_PARSER=y
 CONFIG_SYS_MAXARGS=32
+CONFIG_SYS_PBSIZE=532
 CONFIG_CMD_BOOTZ=y
 # CONFIG_BOOTM_NETBSD is not set
 # CONFIG_BOOTM_PLAN9 is not set