tests: arch: arm: irq_vector_table: don't printk from ISRs

This rather anchient test suite calls printk from within ISRs.
printk() is not declared isr safe, and printk should be avoided from
ISRs due to their stack and cpu time requirements. The test suite
does not use the printk() output in any case, so the printk() output
is simply removed. The README.txt has been updated with the actual
output produced by todays test suite, sans the printk() output.

Signed-off-by: Bjarki Arge Andreasen <[email protected]>

Author: bjarki-andreasen

tests/arch/arm/arm_irq_vector_table/README.txt

@@ -31,10 +31,20 @@ or
 
 Sample Output:
 
-tc_start() - Test Cortex-M3 IRQ installed directly in vector table
-isr0 ran!
-isr1 ran!
-isr2 ran!
-PASS - main.
+Running TESTSUITE vector_table
+===================================================================
+START - test_arm_irq_vector_table
+Test Cortex-M IRQs installed directly in the vector table
+ PASS - test_arm_irq_vector_table in 0.007 seconds
+===================================================================
+TESTSUITE vector_table succeeded
+
+------ TESTSUITE SUMMARY START ------
+
+SUITE PASS - 100.00% [vector_table]: pass = 1, fail = 0, skip = 0, total = 1 duration = 0.007 seconds
+ - PASS - [vector_table.test_arm_irq_vector_table] duration = 0.007 seconds
+
+------ TESTSUITE SUMMARY END ------
+
 ===================================================================
 PROJECT EXECUTION SUCCESSFUL

tests/arch/arm/arm_irq_vector_table/src/arm_irq_vector_table.c

@@ -46,7 +46,6 @@ struct k_sem sem[3];
 
 void isr0(void)
 {
-	printk("%s ran!\n", __func__);
 	k_sem_give(&sem[0]);
 	z_arm_int_exit();
 }
@@ -59,7 +58,6 @@ void isr0(void)
 
 void isr1(void)
 {
-	printk("%s ran!\n", __func__);
 	k_sem_give(&sem[1]);
 	z_arm_int_exit();
 }
@@ -72,7 +70,6 @@ void isr1(void)
 
 void isr2(void)
 {
-	printk("%s ran!\n", __func__);
 	k_sem_give(&sem[2]);
 	z_arm_int_exit();
 }
@@ -97,7 +94,7 @@ void isr2(void)
  */
 ZTEST(vector_table, test_arm_irq_vector_table)
 {
-	printk("Test Cortex-M IRQs installed directly in the vector table\n");
+	TC_PRINT("Test Cortex-M IRQs installed directly in the vector table\n");
 
 	for (int ii = 0; ii < 3; ii++) {
 		irq_enable(_ISR_OFFSET + ii);