skiboot: bump all platforms to skiboot-5.2.0

Let's move to the new stable release of skiboot.

Signed-off-by: Stewart Smith <stewart@linux.vnet.ibm.com>
diff --git a/openpower/configs/barreleye_defconfig b/openpower/configs/barreleye_defconfig
index d3eda3a..5f52640 100644
--- a/openpower/configs/barreleye_defconfig
+++ b/openpower/configs/barreleye_defconfig
@@ -33,8 +33,6 @@
 # skiboot requirements
 BR2_TARGET_SKIBOOT=y
 BR2_TARGET_SKIBOOT_EMBED_PAYLOAD=n
-BR2_SKIBOOT_CUSTOM_VERSION=y
-BR2_SKIBOOT_CUSTOM_VERSION_VALUE="skiboot-5.2.0"
 
 # petitboot requirements
 BR2_ENABLE_LOCALE_PURGE=y
diff --git a/openpower/configs/garrison_defconfig b/openpower/configs/garrison_defconfig
index 4b2010a..eafb6d5 100644
--- a/openpower/configs/garrison_defconfig
+++ b/openpower/configs/garrison_defconfig
@@ -33,8 +33,6 @@
 # skiboot requirements
 BR2_TARGET_SKIBOOT=y
 BR2_TARGET_SKIBOOT_EMBED_PAYLOAD=n
-BR2_SKIBOOT_CUSTOM_VERSION=y
-BR2_SKIBOOT_CUSTOM_VERSION_VALUE="skiboot-5.2.0"
 
 # petitboot requirements
 BR2_ENABLE_LOCALE_PURGE=y
diff --git a/openpower/package/skiboot/Config.in b/openpower/package/skiboot/Config.in
index 796a513..be46ae0 100644
--- a/openpower/package/skiboot/Config.in
+++ b/openpower/package/skiboot/Config.in
@@ -31,7 +31,7 @@
 
 config BR2_SKIBOOT_VERSION
 	string
-	default "skiboot-5.1.15" if BR2_SKIBOOT_LATEST_VERSION
+	default "skiboot-5.2.0" if BR2_SKIBOOT_LATEST_VERSION
 	default BR2_SKIBOOT_CUSTOM_VERSION_VALUE \
 		if BR2_SKIBOOT_CUSTOM_VERSION