[PATCH] block: Add eMMC4.5 packing control unit-tests

Expose the packing control test.
Test the packing control feature under these scenarios:
- Packing expected: entering write packing state, staying in write packing state
- Packing not expected: not entering write packing state when not supposed to
- Mixed states: test the ability to shift from packing to no-packing and back, and the opposite.

Signed-off-by: Lee Susman <lsusman <at> codeaurora.org>
Signed-off-by: Maya Erez <merez <at> codeaurora.org>
---
This patch is dependant on the following patches:
  [PATCH RESEND v7 1/3] mmc: core: Add packed command feature of eMMC4.5
  [PATCH RESEND v7 2/3] mmc: core: Support packed write command for eMMC4.5 device
  [PATCH v2 1/3] mmc: block: Add MMC write packing statistics
  [PATCH v2 2/3] block: Add test-iosched scheduler
  [PATCH v2 3/3] block: Add eMMC4.5 write packed commands unit-tests
  [PATCH v2 1/1] mmc: block: Add write packing control
---
drivers/mmc/card/mmc_block_test.c |  388 +++++++++++++++++++++++++++++++++++++
1 files changed, 388 insertions(+), 0 deletions(-)

diff --git a/drivers/mmc/card/mmc_block_test.c b/drivers/mmc/card/mmc_block_test.c
index 48719fb..b101e42 100644
--- a/drivers/mmc/card/mmc_block_test.c
+++ b/drivers/mmc/card/mmc_block_test.c
 <at>  <at>  -83,6 +83,24  <at>  <at>  enum mmc_block_test_testcases {
 	TEST_CMD23_BITS_16TO29_SET,
 	TEST_CMD23_HDR_BLK_NOT_IN_COUNT,
 	INVALID_CMD_MAX_TESTCASE = TEST_CMD23_HDR_BLK_NOT_IN_COUNT,
+
+	/*