tests: boards: intel_adsp/smoke: fix abs() on unsigned value

Fix complier warning about using abs() with unsigned value.
Since it is being used to calculate differences in clock values,
they needs to be casted into signed 64-bit first to avoid
capping at 32-bit.

Signed-off-by: Daniel Leung <daniel.leung@intel.com>

Author: dcpleung

tests/boards/intel_adsp/smoke/src/cpus.c

@@ -120,7 +120,7 @@ static void core_smoke(void *arg)
 	       clk_ratios[cpu] / 1000, clk_ratios[cpu] % 1000);
 
 	for (int i = 0; i < cpu; i++) {
-		int32_t diff = MAX(1, abs(clk_ratios[i] - clk_ratios[cpu]));
+		int32_t diff = MAX(1, (uint32_t)llabs((int64_t)clk_ratios[i] - clk_ratios[cpu]));
 
 		zassert_true((clk_ratios[cpu] / diff) > 100,
 			     "clocks off by more than 1%%");

tests/boards/intel_adsp/smoke/src/main.c

@@ -36,7 +36,7 @@ ZTEST(intel_adsp, test_clock_calibrate)
 	printk("CLOCK: %lld Hz\n", (1000000ULL * (cyc1 - cyc0)) / host_dt);
 
 	/* Make sure we're within 1% of spec */
-	diff = abs(hz - CONFIG_SYS_CLOCK_HW_CYCLES_PER_SEC);
+	diff = (uint32_t)llabs((int64_t)hz - CONFIG_SYS_CLOCK_HW_CYCLES_PER_SEC);
 	zassert_true((hz / MIN(1, diff)) > 100, "clock rate wrong");
 }