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/libretech_all_h3_cc_h3_defconfig b/configs/libretech_all_h3_cc_h3_defconfig
index 5275fdc..6b9fadd 100644
--- a/configs/libretech_all_h3_cc_h3_defconfig
+++ b/configs/libretech_all_h3_cc_h3_defconfig
@@ -6,6 +6,7 @@
 CONFIG_DRAM_CLK=672
 CONFIG_MMC_SUNXI_SLOT_EXTRA=2
 # CONFIG_SYS_MALLOC_CLEAR_ON_INIT is not set
+CONFIG_SYS_PBSIZE=1024
 CONFIG_SUN8I_EMAC=y
 CONFIG_USB_EHCI_HCD=y
 CONFIG_USB_OHCI_HCD=y