lib/mpi: fix spelling mistakes

Fix some spelling mistakes in comments:
flaged ==> flagged
bufer ==> buffer
multipler ==> multiplier
MULTIPLER ==> MULTIPLIER
leaset ==> least
chnage ==> change

Link: https://lkml.kernel.org/r/20210604074401.12198-1-thunder.leizhen@huawei.com
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

lib/mpi/mpiutil.c

@@ -80,7 +80,7 @@ EXPORT_SYMBOL_GPL(mpi_const);
 /****************
  * Note:  It was a bad idea to use the number of limbs to allocate
  *	  because on a alpha the limbs are large but we normally need
- *	  integers of n bits - So we should chnage this to bits (or bytes).
+ *	  integers of n bits - So we should change this to bits (or bytes).
  *
  *	  But mpi_alloc is used in a lot of places :-)
  */