mcomp: Remove an obsolete undef.

The macro was removed in 6724676.

Change-Id: I412c24aac49bd1ff60a331a30933e0d8ae3f2dd5

vp10/encoder/mcomp.c

diff --git a/vp10/encoder/mcomp.c b/vp10/encoder/mcomp.c
index 007fe0c..1ba2e2f 100644
--- a/vp10/encoder/mcomp.c
+++ b/vp10/encoder/mcomp.c
@@ -780,7 +780,6 @@
 }
 
 #undef MVC
-#undef PRE
 #undef CHECK_BETTER
 
 static INLINE int check_bounds(const MACROBLOCK *x, int row, int col,

vp9/encoder/vp9_mcomp.c

diff --git a/vp9/encoder/vp9_mcomp.c b/vp9/encoder/vp9_mcomp.c
index bbc2e08..f3ffe35 100644
--- a/vp9/encoder/vp9_mcomp.c
+++ b/vp9/encoder/vp9_mcomp.c
@@ -825,7 +825,6 @@
 }
 
 #undef MVC
-#undef PRE
 #undef CHECK_BETTER
 
 static INLINE int check_bounds(const MACROBLOCK *x, int row, int col,