Convert CONFIG_SYS_I2C_EEPROM_ADDR et al to Kconfig

- Rename usages of CONFIG_SYS_DEF_EEPROM_ADDR to CONFIG_SYS_I2C_EEPROM_ADDR
  based on current usage.
- Convert CONFIG_SYS_I2C_EEPROM_ADDR, CONFIG_SYS_I2C_EEPROM_ADDR_LEN,
  CONFIG_SYS_I2C_EEPROM_BUS, CONFIG_CONFIG_SYS_EEPROM_SIZE
  CONFIG_SYS_EEPROM_PAGE_WRITE_BITS and CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS
  to Kconfig.  We move these symbols around a bit and add appropriate
  dependencies to them.  In some cases, we now add a correct default value
  as well.

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/sifive_unmatched_defconfig b/configs/sifive_unmatched_defconfig
index bdd045a..88b74a9 100644
--- a/configs/sifive_unmatched_defconfig
+++ b/configs/sifive_unmatched_defconfig
@@ -30,6 +30,7 @@
 CONFIG_CMD_USB=y
 CONFIG_SYS_RELOC_GD_ENV_ADDR=y
 CONFIG_SPL_CLK=y
+CONFIG_SYS_I2C_EEPROM_ADDR=0x54
 CONFIG_E1000=y
 CONFIG_NVME=y
 CONFIG_PCI=y