bootstate: use structure pointers for scheduling callbacks

The GCC 4.9.2 update showed that the boot_state_init_entry
structures were being padded and assumed to be aligned in to an
increased size. The bootstate scheduler for static entries,
boot_state_schedule_static_entries(), was then calculating the
wrong values within the array. To fix this just use a pointer to
the boot_state_init_entry structure that needs to be scheduled.

In addition to the previous issue noted above, the .bs_init
section was sitting in the read only portion of the image while
the fields within it need to be writable. Also, the
boot_state_schedule_static_entries() was using symbol comparison
to terminate a loop which in C can lead the compiler to always
evaluate the loop at least once since the language spec indicates
no 2 symbols can be the same value.

Change-Id: I6dc5331c2979d508dde3cd5c3332903d40d8048b
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: http://review.coreboot.org/8699
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <pgeorgi@google.com>

src/southbridge/intel/common/spi.c

@@ -366,9 +366,7 @@ static void spi_init_cb(void *unused)
 	spi_init();
 }
 
-BOOT_STATE_INIT_ENTRIES(spi_init_bscb) = {
-	BOOT_STATE_INIT_ENTRY(BS_DEV_INIT, BS_ON_ENTRY, spi_init_cb, NULL),
-};
+BOOT_STATE_INIT_ENTRY(BS_DEV_INIT, BS_ON_ENTRY, spi_init_cb, NULL);
 #endif
 
 int spi_claim_bus(struct spi_slave *slave)