StdLib: Modify the memory allocation routines to not be dependent upon the internal structure of the EDK II memory pool.

StdLib/LibC/StdLib/Malloc.c
Create a private data structure, CPOOL_HEAD, which contains housekeeping information for StdLib’s memory allocation functions.  An instance of this structure is prepended to every chunk of allocated memory.  The structure links the allocation into a doubly-linked list and keeps track of the size of each allocation unit.  This information is then available for use by the realloc function.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Daryl McDaniel <daryl.mcdaniel@intel.com>
Reviewed-by: Jaben Carsey <jaben.carsey@intel.com>
Reviewed-by: Erik Bjorge <erik.c.bjorge@intel.com>
Reviewed-by:  Rosenbaum, Lee G <lee.g.rosenbaum@intel.com>



git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@15319 6f19259b-4bc3-4df7-8a09-765794883524
 1.Add code to check the pointer  'CorrectedPath' in Ls.c line 460 before referenced. 2.Not use  explicit comparisons to TRUE or FALSE for Boolean variable in Ls.c. 3.Add doxygen tags in comment and return type for 'ToLower' in ShellProtocol.c. 

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Shumin Qiu <shumin.qiu@intel.com>
Reviewed-by: Jaben Carsey <Jaben.carsey@intel.com>


git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@15320 6f19259b-4bc3-4df7-8a09-765794883524