C2 VTS: Fix St12out_of_range

use stoul instead of stol as the data being converted is unsigned.

Bug: 155138755
Test: VtsHalMediaC2V1_0TargetComponentTest

Change-Id: I5d7079538b5707c68454fa453667744758c9122a

media/codec2/hidl/1.0/vts/functional/component/VtsHalMediaC2V1_0TargetComponentTest.cpp

@@ -330,7 +330,7 @@ class Codec2ComponentInputTests
 TEST_P(Codec2ComponentInputTests, InputBufferTest) {
     description("Tests for different inputs");
 
-    uint32_t flags = std::stol(std::get<2>(GetParam()));
+    uint32_t flags = std::stoul(std::get<2>(GetParam()));
     bool isNullBuffer = !std::get<3>(GetParam()).compare("true");
     if (isNullBuffer)
         ALOGD("Testing for null input buffer with flag : %u", flags);