[PATCH v2] env: add prototypes for weak function

[Patrick Delaunay]

This patch adds prototypes for several weak functions:
- env_ext4_get_intf
- env_ext4_get_dev_part
- env_get_location

It solves the following warnings when compiling with W=1
on stm32mp1 board:

board/st/stm32mp1/stm32mp1.c:849:19: warning: no previous prototype for 'env_get_location' [-Wmissing-prototypes]
 enum env_location env_get_location(enum env_operation op, int prio)
                   ^~~~~~~~~~~~~~~~
board/st/stm32mp1/stm32mp1.c:876:13: warning: no previous prototype for 'env_ext4_get_intf' [-Wmissing-prototypes]
 const char *env_ext4_get_intf(void)
             ^~~~~~~~~~~~~~~~~
board/st/stm32mp1/stm32mp1.c:889:13: warning: no previous prototype for 'env_ext4_get_dev_part' [-Wmissing-prototypes]
 const char *env_ext4_get_dev_part(void)
             ^~~~~~~~~~~~~~~~~~~~~

Signed-off-by: Patrice Chotard <patrice.chotard at st.com>
Signed-off-by: Patrick Delaunay <patrick.delaunay at st.com>
---

Changes in v2:
- clarify the comment on the added prototype

 include/env_internal.h | 31 +++++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)

diff --git a/include/env_internal.h b/include/env_internal.h
index 90a4df8a72..3f13a90326 100644
--- a/include/env_internal.h
+++ b/include/env_internal.h
@@ -209,6 +209,37 @@ struct env_driver {
 
 extern struct hsearch_data env_htab;
 
+/**
+ * env_ext4_get_intf() - Provide the interface for env in EXT4
+ *
+ * It is a weak function allowing board to overidde the default interface for
+ * U-Boot env in EXT4: CONFIG_ENV_EXT4_INTERFACE
+ *
+ * @return string of interface, empty if not supported
+ */
+const char *env_ext4_get_intf(void);
+
+/**
+ * env_ext4_get_dev_part() - Provide the device and partition for env in EXT4
+ *
+ * It is a weak function allowing board to overidde the default device and
+ * partition used for U-Boot env in EXT4: CONFIG_ENV_EXT4_DEVICE_AND_PART
+ *
+ * @return string of device and partition
+ */
+const char *env_ext4_get_dev_part(void);
+
+/**
+ * env_get_location()- Provide the best location for the U-Boot environment
+ *
+ * It is a weak function allowing board to overidde the environment location
+ *
+ * @op: operations performed on the environment
+ * @prio: priority between the multiple environments, 0 being the
+ *        highest priority
+ * @return  an enum env_location value on success, or -ve error code.
+ */
+enum env_location env_get_location(enum env_operation op, int prio);
 #endif /* DO_DEPS_ONLY */
 
 #endif /* _ENV_INTERNAL_H_ */
-- 
2.17.1