[nrf toup] Zephyr: Fix the data type for time

We use subtraction operation over time, so, it has to be signed.

Fixes "[nrf toup] Use 64bit data type to store time".

Fixes SHEL-2731.

Signed-off-by: Chaitanya Tata <Chaitanya.Tata@nordicsemi.no>

Author: krish2718

src/utils/os.h

@@ -9,7 +9,7 @@
 #ifndef OS_H
 #define OS_H
 
-typedef uint64_t os_time_t;
+typedef int64_t os_time_t;
 
 /**
  * os_sleep - Sleep (sec, usec)