Fix typo in cache auto-configurations

Make sure that the EhCache support is triggered if
`spring.cache.ehcache.config` is set and the cache type is set to `auto`.

Same thing for Hazelcast.

Closes gh-3227

spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/cache/EhCacheCacheConfiguration.java

@@ -71,7 +71,7 @@ class EhCacheCacheConfiguration {
 	static class ConfigAvailableCondition extends CacheConfigFileCondition {
 
 		public ConfigAvailableCondition() {
-			super("EhCache", "spring.config.ehcache", "classpath:/ehcache.xml");
+			super("EhCache", "spring.cache.ehcache", "classpath:/ehcache.xml");
 		}
 
 	}

spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/cache/HazelcastCacheConfiguration.java

@@ -81,7 +81,7 @@ class HazelcastCacheConfiguration {
 	static class ConfigAvailableCondition extends CacheConfigFileCondition {
 
 		public ConfigAvailableCondition() {
-			super("Hazelcast", "spring.config.hazelcast", "file:./hazelcast.xml",
+			super("Hazelcast", "spring.cache.hazelcast", "file:./hazelcast.xml",
 					"classpath:/hazelcast.xml");
 		}