Revert "Copy structs using assignment, not memcpy()."

This reverts commit d1965788249d7e22cdde4021d452cf0dc6c6b9bd.

This breaks my build on Gentoo running gcc 4.9.2

libgps_shm.c: In function 'int gps_shm_read(gps_data_t*)':
libgps_shm.c:122:12: error: no match for 'operator=' (operand types are
'gps_data_t' and 'volatile gps_data_t')
  noclobber = shared->gpsdata;
            ^
libgps_shm.c:122:12: note: candidate is:
In file included from gpsd.h:350:0,
                 from libgps_shm.c:30:
gps.h:1918:8: note: gps_data_t& gps_data_t::operator=(const gps_data_t&)
 struct gps_data_t {
        ^
gps.h:1918:8: note:   no known conversion for argument 1 from 'volatile
gps_data_t' to 'const gps_data_t&'

1 files changed, 1 insertions, 1 deletions

diff --git a/ntpshmread.c b/ntpshmread.c
index 498b78ee..c75410be 100644
--- a/ntpshmread.c
+++ b/ntpshmread.c
@@ -85,7 +85,7 @@ enum segstat_t ntp_read(struct shmTime *shm_in, struct shm_stat_t *shm_stat, con
      * page size).
      */
     memory_barrier();
-    shmcopy = *shm;
+    memcpy((void *)&shmcopy, (void *)shm, sizeof(struct shmTime));
 
     /*
      * An update consumer such as ntpd should zero the valid flag at this point.