doc: replace @return by Return:

Sphinx expects Return: and not @return to indicate a return value.

find . -name '*.c' -exec \
sed -i 's/^\(\s\)\*\(\s*\)@return\(\s\)/\1*\2Return:\3/' {} \;

find . -name '*.h' -exec \
sed -i 's/^\(\s\)\*\(\s*\)@return\(\s\)/\1*\2Return:\3/' {} \;

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
diff --git a/env/common.c b/env/common.c
index ee957c0..f9226e0 100644
--- a/env/common.c
+++ b/env/common.c
@@ -47,7 +47,7 @@
  *
  * @param varname	Environment variable to set
  * @param value		Value to set it to
- * @return 0 if ok, 1 on error
+ * Return: 0 if ok, 1 on error
  */
 int env_set_ulong(const char *varname, ulong value)
 {
@@ -62,7 +62,7 @@
  *
  * @param varname	Environment variable to set
  * @param value		Value to set it to
- * @return 0 if ok, 1 on error
+ * Return: 0 if ok, 1 on error
  */
 int env_set_hex(const char *varname, ulong value)
 {
@@ -208,7 +208,7 @@
  * @param base		Number base to use (normally 10, or 16 for hex)
  * @param default_val	Default value to return if the variable is not
  *			found
- * @return the decoded value, or default_val if not found
+ * Return: the decoded value, or default_val if not found
  */
 ulong env_get_ulong(const char *name, int base, ulong default_val)
 {