cortex-m: warnings: Address -Wextra warnings

`#defines` do NOT sepecify a type. They will either adopt a native
system type or type of the value that was passed into the expression.
This can lead to warnings such as, "warning: comparison of integer
expressions of different signedness: 'uint32_t' {aka 'unsigned int'}
and 'int' [-Wsign-compare]".

By casting expressions, such as `MAX_TICKS` to `k_ticks_t`, we can
force the appropriate types and resolve these warnings.

Signed-off-by: Zachary J. Fields <[email protected]>

Author: zfields

drivers/timer/cortex_m_systick.c

@@ -15,7 +15,7 @@
 
 #define CYC_PER_TICK (sys_clock_hw_cycles_per_sec()	\
 		      / CONFIG_SYS_CLOCK_TICKS_PER_SEC)
-#define MAX_TICKS ((COUNTER_MAX / CYC_PER_TICK) - 1)
+#define MAX_TICKS ((k_ticks_t)(COUNTER_MAX / CYC_PER_TICK) - 1)
 #define MAX_CYCLES (MAX_TICKS * CYC_PER_TICK)
 
 /* Minimum cycles in the future to try to program.  Note that this is
@@ -27,7 +27,7 @@
  * masked.  Choosing a fraction of a tick is probably a good enough
  * default, with an absolute minimum of 1k cyc.
  */
-#define MIN_DELAY MAX(1024, (CYC_PER_TICK/16))
+#define MIN_DELAY MAX(1024U, ((uint32_t)CYC_PER_TICK/16U))
 
 #define TICKLESS (IS_ENABLED(CONFIG_TICKLESS_KERNEL))