libblock: Add task stack size bdbuf configuration

The task stack size for the swap-out and worker tasks is now
configurable.  The bdbuf task resources are now included in the work
space size estimate.
libblock: Remove const qualifier from bdbuf API

This allows addtion of per disk statistics for example.
libblock: Remove explicit bds_per_group parameter
libblock: Simplify disk management

Add block_count and media_blocks_per_block to rtems_disk_device.  Add
and use rtems_disk_init_phys() and rtems_disk_init_log().
libblock: Move rtems_bdbuf_get_media_block() call

Move rtems_bdbuf_get_media_block() call inside the bdbuf lock.
dosfs: Fix format request with sectors per cluster
Revert "libtests/complex: Avoid generated files"

This reverts commit a80a108d447d596e476611108cd468ec993be4a6.
Revert "libtests/math*: Avoid generated files"

This reverts commit 6a5bd1c65c005457455db344f2ee831d7a5cf99b.
Revert "Revert "libtests/math*: Avoid generated files""

This reverts commit 87c8d8aba6a9582ca5eeacd332b5b107e26ea50f.
Revert "Revert "libtests/complex: Avoid generated files""

This reverts commit 0c2d8ec48a116cadb86564bc1226e308e197d4c1.
sptests - Eliminate missing prototype warnings
samples - Eliminate missing prototype warnings
Fix C files which had two semi-colons at EOL
powerpc: Simplify context switch

PowerPC cores with the SPE (Signal Processing Extension) have 64-bit
general-purpose registers.  The SPE context switch code has been merged
with the standard context switch code.  The context switch may use cache
operations to increase the performance.  It will be ensured that the
context is 32-byte aligned (PPC_DEFAULT_CACHE_LINE_SIZE).  This
increases the overall memory size of the context area in the thread
control block slightly.  The general-purpose registers GPR2 and GPR13
are no longer part of the context.  The BSP must initialize these
registers during startup (usually initialized by the __eabi() function).

The new BSP option BSP_USE_DATA_CACHE_BLOCK_TOUCH can be used to enable
the dcbt instruction in the context switch.

The new BSP option BSP_USE_SYNC_IN_CONTEXT_SWITCH can be used to enable
sync and isync instructions in the context switch.  This should be not
necessary in most cases.
bsp/qoriq: New BSP option

New BSP option BSP_USE_DATA_CACHE_BLOCK_TOUCH.
bsps/powerpc: Add load section for .nocache
libblock: Add read-ahead task

Read-ahead requests were previously executed in the context of the
reading task.  This blocks the reading task until the complete read
with read-ahead transfer is finished.  A read-ahead task is introduced
to off-load the read-ahead transfer.  This allows the reading task to
work with the requested block more quickly.  The read-ahead is triggered
after two misses of ascending consecutive blocks or a read hit of a
block read by the most-recent read-ahead transfer.  The read-ahead
feature is configurable and can be disabled.
dosfs: Fix for no space left on device condition

The file size was wrong in the no space left on device condition.  This
resulted in turn in a read of an invalid block which lead to an EIO
error status.
libtests/block05: Fix warnings
bsp/t32mppc: Fix Trace32 configuration file