Fix secp256k1_fe_inv_all_var parameter order

Rearranged secp256k1_fe_inv_all_var parameters so length is after array.
Text editor removed some trailing whitespaces.

src/field.h

@@ -110,7 +110,7 @@ static void secp256k1_fe_inv_var(secp256k1_fe *r, const secp256k1_fe *a);
 /** Calculate the (modular) inverses of a batch of field elements. Requires the inputs' magnitudes to be
  *  at most 8. The output magnitudes are 1 (but not guaranteed to be normalized). The inputs and
  *  outputs must not overlap in memory. */
-static void secp256k1_fe_inv_all_var(size_t len, secp256k1_fe *r, const secp256k1_fe *a);
+static void secp256k1_fe_inv_all_var(secp256k1_fe *r, const secp256k1_fe *a, size_t len);
 
 /** Convert a field element to the storage type. */
 static void secp256k1_fe_to_storage(secp256k1_fe_storage *r, const secp256k1_fe *a);

src/field_impl.h

@@ -260,7 +260,7 @@ static void secp256k1_fe_inv_var(secp256k1_fe *r, const secp256k1_fe *a) {
 #endif
 }
 
-static void secp256k1_fe_inv_all_var(size_t len, secp256k1_fe *r, const secp256k1_fe *a) {
+static void secp256k1_fe_inv_all_var(secp256k1_fe *r, const secp256k1_fe *a, size_t len) {
     secp256k1_fe u;
     size_t i;
     if (len < 1) {

src/group_impl.h

@@ -89,7 +89,7 @@ static void secp256k1_ge_set_all_gej_var(size_t len, secp256k1_ge *r, const secp
     }
 
     azi = (secp256k1_fe *)checked_malloc(cb, sizeof(secp256k1_fe) * count);
-    secp256k1_fe_inv_all_var(count, azi, az);
+    secp256k1_fe_inv_all_var(azi, az, count);
     free(az);
 
     count = 0;

src/tests.c

@@ -1733,18 +1733,18 @@ void run_field_inv_all_var(void) {
     secp256k1_fe x[16], xi[16], xii[16];
     int i;
     /* Check it's safe to call for 0 elements */
-    secp256k1_fe_inv_all_var(0, xi, x);
+    secp256k1_fe_inv_all_var(xi, x, 0);
     for (i = 0; i < count; i++) {
         size_t j;
         size_t len = secp256k1_rand_int(15) + 1;
         for (j = 0; j < len; j++) {
             random_fe_non_zero(&x[j]);
         }
-        secp256k1_fe_inv_all_var(len, xi, x);
+        secp256k1_fe_inv_all_var(xi, x, len);
         for (j = 0; j < len; j++) {
             CHECK(check_fe_inverse(&x[j], &xi[j]));
         }
-        secp256k1_fe_inv_all_var(len, xii, xi);
+        secp256k1_fe_inv_all_var(xii, xi, len);
         for (j = 0; j < len; j++) {
             CHECK(check_fe_equal(&x[j], &xii[j]));
         }
@@ -1930,7 +1930,7 @@ void test_ge(void) {
                 zs[i] = gej[i].z;
             }
         }
-        secp256k1_fe_inv_all_var(4 * runs + 1, zinv, zs);
+        secp256k1_fe_inv_all_var(zinv, zs, 4 * runs + 1);
         free(zs);
     }