kill sprintf
fix unused variables
for LIBSA_PRINTF_WIDTH_SUPPORT,
Fix right and left-adjusting padding.
add Watchdog Timer support for i.MX51.
* GPIO interrupts of i.MX5 are divided into two groups.
  add IMX_GPIO_INTR_SPLIT option
* Support GPIO both edge trigger interrupt.
Small changes:
 - rename elf_load_file() to elf_load_interp()
 - use the correct type for 'nused'
 - remove useless cases
 - reorder a kmem_alloc

ok christos@
'newrt' is not supposed to be NULL. Therefore, the NULL-check in the if()
is pointless; and even if 'newrt' were NULL, 'rt' would be dereferenced
later. This is not a bug.

CID 270855

ok christos@
Remove reference to simplelock
Fix a potential - but very unlikely - NULL pointer dereference.
(it does not introduce a new error code for open(), since
 pathbuf_copyin() is already there and can return ENOMEM)

Found by my code scanner.
Add SPI driver.
i.MX51 have two eCSPI, and one CSPI.
Fix SDHC clocks.
Add mtsleep(9) and a description of how it, tsleep(9), and wakeup(9)
should all be replaced with condvar(9).

While here clear out the lock(9) reference(s) and the obsoleted example.

Based on misc/48671
Bump date for previous
New sentence, new line; slight wording improvements.
Add a few xorg lint libraries.
Make sure r1 is preserved _rtld_bind_start.