Build audio.primary.* with BOARD_VNDK_VERSION

Add libhardware_headers to the dependency list since
hardware/libhardware/include is not added to the global include path
when building with BOARD_VNDK_VERSION. Also, a few headers - pthread.h,
unistd.h - are explicitly added.

Bug: 37342627
Test: BOARD_VNDK_VERSION=current m -j audio.primary.msm8998
Change-Id: I908aed7cf9c5aa970d1e4486dcff32d20d44aebd
diff --git a/hal/audio_extn/hwdep_cal.c b/hal/audio_extn/hwdep_cal.c
index 811db3e..07269d1 100644
--- a/hal/audio_extn/hwdep_cal.c
+++ b/hal/audio_extn/hwdep_cal.c
@@ -24,6 +24,7 @@
 #include <dlfcn.h>
 #include <fcntl.h>
 #include <sys/ioctl.h>
+#include <unistd.h>
 #include <cutils/log.h>
 #include <audio_hw.h>
 #include "audio_extn.h"
diff --git a/hal/audio_extn/sndmonitor.c b/hal/audio_extn/sndmonitor.c
index 3c91dda..9b44742 100644
--- a/hal/audio_extn/sndmonitor.c
+++ b/hal/audio_extn/sndmonitor.c
@@ -36,6 +36,7 @@
 #include <fcntl.h>
 #include <sys/stat.h>
 #include <sys/poll.h>
+#include <pthread.h>
 #include <cutils/list.h>
 #include <cutils/hashmap.h>
 #include <cutils/log.h>
diff --git a/hal/audio_extn/soundtrigger.c b/hal/audio_extn/soundtrigger.c
index 112bd1e..3417c72 100644
--- a/hal/audio_extn/soundtrigger.c
+++ b/hal/audio_extn/soundtrigger.c
@@ -21,6 +21,8 @@
 #include <stdbool.h>
 #include <stdlib.h>
 #include <dlfcn.h>
+#include <pthread.h>
+#include <unistd.h>
 #include <cutils/log.h>
 #include "audio_hw.h"
 #include "audio_extn.h"
diff --git a/hal/audio_extn/usb.c b/hal/audio_extn/usb.c
index 6b3ee7b..86b75d8 100644
--- a/hal/audio_extn/usb.c
+++ b/hal/audio_extn/usb.c
@@ -22,6 +22,7 @@
 #include <cutils/log.h>
 #include <cutils/str_parms.h>
 #include <sys/ioctl.h>
+#include <unistd.h>
 #include <fcntl.h>
 #include <sys/stat.h>
 #include <system/audio.h>
diff --git a/hal/audio_extn/utils.c b/hal/audio_extn/utils.c
index bd39f0b..424f177 100644
--- a/hal/audio_extn/utils.c
+++ b/hal/audio_extn/utils.c
@@ -22,6 +22,7 @@
 #include <cutils/config_utils.h>
 #include <stdlib.h>
 #include <dlfcn.h>
+#include <unistd.h>
 #include <cutils/str_parms.h>
 #include <cutils/log.h>
 #include <cutils/misc.h>