CDRIVER-4394 fix function names in range index docs (#1231)

Author: jmikola

src/libmongoc/doc/mongoc_client_encryption_encrypt_range_opts_set_min_max.rst

@@ -9,7 +9,7 @@ Synopsis
 .. code-block:: c
 
     void
-    mongoc_client_encryption_encrypt_opts_set_min_max (
+    mongoc_client_encryption_encrypt_range_opts_set_min_max (
          mongoc_client_encryption_encrypt_range_opts_t *range_opts, 
          const bson_value_t *min,
          const bson_value_t *max);

src/libmongoc/doc/mongoc_client_encryption_encrypt_range_opts_set_precision.rst

@@ -9,7 +9,7 @@ Synopsis
 .. code-block:: c
 
     void
-    mongoc_client_encryption_encrypt_opts_set_precision (
+    mongoc_client_encryption_encrypt_range_opts_set_precision (
          mongoc_client_encryption_encrypt_range_opts_t *range_opts, int32_t precision);
 
 .. important:: The |qenc:range-is-experimental| |qenc:api-is-experimental|

src/libmongoc/doc/mongoc_client_encryption_encrypt_range_opts_set_sparsity.rst

@@ -9,7 +9,7 @@ Synopsis
 .. code-block:: c
 
     void
-    mongoc_client_encryption_encrypt_opts_set_sparsity (
+    mongoc_client_encryption_encrypt_range_opts_set_sparsity (
          mongoc_client_encryption_encrypt_range_opts_t *range_opts, int64_t sparsity);
 
 .. important:: The |qenc:range-is-experimental| |qenc:api-is-experimental|