Convert CONFIG_BOOT_RETRY_TIME et al to Kconfig

This converts the following to Kconfig:
   CONFIG_BOOT_RETRY_TIME
   CONFIG_BOOT_RETRY_MIN
   CONFIG_RESET_TO_RETRY

We also introduce CONFIG_BOOT_RETRY to gate these options, and clean up
the associated Makefile entry and C code for picking default values of
CONFIG_BOOT_RETRY_MIN.

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/eb_cpu5282_internal_defconfig b/configs/eb_cpu5282_internal_defconfig
index f9a00b8..240bb00 100644
--- a/configs/eb_cpu5282_internal_defconfig
+++ b/configs/eb_cpu5282_internal_defconfig
@@ -7,6 +7,9 @@
 CONFIG_SYS_LOAD_ADDR=0x20000
 CONFIG_SYS_EXTRA_OPTIONS="SYS_MONITOR_BASE=0xF0000418"
 CONFIG_BOOTDELAY=5
+CONFIG_BOOT_RETRY=y
+CONFIG_BOOT_RETRY_TIME=-1
+CONFIG_RESET_TO_RETRY=y
 CONFIG_USE_BOOTCOMMAND=y
 CONFIG_BOOTCOMMAND="printenv"
 # CONFIG_DISPLAY_BOARDINFO is not set