arch: arm: Fix make export for armv7-a SoCs

Summary:
- I noticed that make export does not work with swama5d4-ek:knsh
- This commit fixes this issue.
- NOTE: apps/Makefile also needs to be updated.

Impact:
- CONFIG_BUILD_KERNEL=y only

Testing:
- Build (make and make export) with sama5d4-ek:knsh

Signed-off-by: Masayuki Ishikawa <Masayuki.Ishikawa@jp.sony.com>

arch/arm/src/a1x/Make.defs

@@ -24,6 +24,9 @@
 HEAD_ASRC  = arm_vectortab.S
 
 ifeq ($(CONFIG_BUILD_KERNEL),y)
+crt0$(OBJEXT): crt0.c
+	$(CC) $(CFLAGS) -c armv7-a$(DELIM)crt0.c -o crt0$(OBJEXT)
+
 STARTUP_OBJS = crt0$(OBJEXT)
 endif
 

arch/arm/src/am335x/Make.defs

@@ -24,6 +24,9 @@
 HEAD_ASRC  = arm_vectortab.S
 
 ifeq ($(CONFIG_BUILD_KERNEL),y)
+crt0$(OBJEXT): crt0.c
+	$(CC) $(CFLAGS) -c armv7-a$(DELIM)crt0.c -o crt0$(OBJEXT)
+
 STARTUP_OBJS = crt0$(OBJEXT)
 endif
 

arch/arm/src/armv7-a/crt0.c

@@ -29,6 +29,8 @@
 
 #include <nuttx/addrenv.h>
 
+#include "svcall.h"
+
 #ifdef CONFIG_BUILD_KERNEL
 
 /****************************************************************************

arch/arm/src/imx6/Make.defs

@@ -24,6 +24,9 @@
 HEAD_ASRC  = arm_vectortab.S
 
 ifeq ($(CONFIG_BUILD_KERNEL),y)
+crt0$(OBJEXT): crt0.c
+	$(CC) $(CFLAGS) -c armv7-a$(DELIM)crt0.c -o crt0$(OBJEXT)
+
 STARTUP_OBJS = crt0$(OBJEXT)
 endif
 

arch/arm/src/sama5/Make.defs

@@ -24,6 +24,9 @@
 HEAD_ASRC  = arm_vectortab.S
 
 ifeq ($(CONFIG_BUILD_KERNEL),y)
+crt0$(OBJEXT): crt0.c
+	$(CC) $(CFLAGS) -c armv7-a$(DELIM)crt0.c -o crt0$(OBJEXT)
+
 STARTUP_OBJS = crt0$(OBJEXT)
 endif