Call xxx_timer_initialize from clock subsystem

Call xxx_timer_initialize from clock subsystem to make timer ready for use as soon as possiblei and revert the workaround:

commit 0863e771a9
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Fri Apr 26 07:24:57 2019 -0600

    Revert "sched/clock/clock_initialize.c:  clock_inittime() needs to be done with CONFIG_SCHED_TICKLESS and clock_initialize should skip clock_inittime() for external RTC case since the RTC isn't ready yet."

    This reverts commit 2bc709d4b9.

    Commit 2bc709d4b9 was intended to handle the case where up_timer_gettime may not start from zero case.  However, this change has the side-effect of breaking every implementation of tickless mode:  After this change the tickless timer structures are used before they are initialized in clock_inittime().  Initialization happens later when up_initialize is called() when arm_timer_initialize().

    Since the tickless mode timer is very special, one solution might be to

    1. Rename xxx_timer_initialize to up_timer_initialize
    2  Move up_timer_initialize to include/nuttx/arch.h
    3.  Call it from clock subsystem instead up_initialize

    Basically, this change make timer initialization almost same as rtc initialization(up_rtc_initialize).

    For now, however, we just need to revert the change.

arch/misoc/src/common/misoc.h

@@ -63,16 +63,6 @@
 
 #ifndef __ASSEMBLY__
 
-/****************************************************************************
- * Name: misoc_timer_initialize
- *
- * Description:
- *   Initialize and start the system timer.
- *
- ****************************************************************************/
-
-void misoc_timer_initialize(void);
-
 /****************************************************************************
  * Name: flush_cpu_dcache
  *

arch/misoc/src/common/misoc_timerisr.c

@@ -108,7 +108,7 @@ int misoc_timer_isr(int irq, void *context, void *arg)
 }
 
 /****************************************************************************
- * Function:  misoc_timer_initialize
+ * Function:  up_timer_initialize
  *
  * Description:
  *   This function is called during start-up to initialize
@@ -116,7 +116,7 @@ int misoc_timer_isr(int irq, void *context, void *arg)
  *
  ****************************************************************************/
 
-void misoc_timer_initialize(void)
+void up_timer_initialize(void)
 {
   /* Clear event pending */
 

arch/misoc/src/lm32/lm32_initialize.c

@@ -75,10 +75,6 @@ void up_initialize(void)
   rpmsg_serialinit();
 #endif
 
-  /* Initialize the system timer */
-
-  misoc_timer_initialize();
-
 #ifdef CONFIG_MM_IOB
   /* Initialize IO buffering */
 

arch/misoc/src/minerva/minerva_initialize.c

@@ -75,10 +75,6 @@ void up_initialize(void)
   rpmsg_serialinit();
 #endif
 
-  /* Initialize the system timer */
-
-  misoc_timer_initialize();
-
 #ifdef CONFIG_MM_IOB
   /* Initialize IO buffering */