Convert CONFIG_SPL_INIT_MINIMAL et al to Kconfig

This converts the following to Kconfig:
   CONFIG_SPL_INIT_MINIMAL
   CONFIG_SPL_FLUSH_IMAGE
   CONFIG_SPL_SKIP_RELOCATE

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/arch/powerpc/cpu/mpc8xxx/Makefile b/arch/powerpc/cpu/mpc8xxx/Makefile
index bec891d..e3a536d 100644
--- a/arch/powerpc/cpu/mpc8xxx/Makefile
+++ b/arch/powerpc/cpu/mpc8xxx/Makefile
@@ -5,10 +5,12 @@
 MINIMAL=
 
 ifdef CONFIG_SPL_BUILD
+ifndef CONFIG_TPL_BUILD
 ifdef CONFIG_SPL_INIT_MINIMAL
 MINIMAL=y
 endif
 endif
+endif
 
 ifdef MINIMAL
 
diff --git a/arch/powerpc/cpu/mpc8xxx/law.c b/arch/powerpc/cpu/mpc8xxx/law.c
index cf03f41..713ff17 100644
--- a/arch/powerpc/cpu/mpc8xxx/law.c
+++ b/arch/powerpc/cpu/mpc8xxx/law.c
@@ -79,7 +79,7 @@
 }
 
 #if !defined(CONFIG_NAND_SPL) && \
-	(!defined(CONFIG_SPL_BUILD) || !defined(CONFIG_SPL_INIT_MINIMAL))
+	(!defined(CONFIG_SPL_BUILD) || !CONFIG_IS_ENABLED(INIT_MINIMAL))
 static int get_law_entry(u8 i, struct law_entry *e)
 {
 	u32 lawar;
@@ -110,7 +110,7 @@
 }
 
 #if !defined(CONFIG_NAND_SPL) && \
-	(!defined(CONFIG_SPL_BUILD) || !defined(CONFIG_SPL_INIT_MINIMAL))
+	(!defined(CONFIG_SPL_BUILD) || !CONFIG_IS_ENABLED(INIT_MINIMAL))
 int set_last_law(phys_addr_t addr, enum law_size sz, enum law_trgt_if id)
 {
 	u32 idx;