patch 8.2.4402: missing parenthesis may cause unexpected problems

Problem:    Missing parenthesis may cause unexpected problems.
Solution:   Add more parenthesis is macros. (closes #9788)
diff --git a/src/search.c b/src/search.c
index f4c2c87..dbc766f 100644
--- a/src/search.c
+++ b/src/search.c
@@ -4300,15 +4300,15 @@
 // bonus if the first letter is matched
 #define FIRST_LETTER_BONUS 15
 // penalty applied for every letter in str before the first match
-#define LEADING_LETTER_PENALTY -5
+#define LEADING_LETTER_PENALTY (-5)
 // maximum penalty for leading letters
-#define MAX_LEADING_LETTER_PENALTY -15
+#define MAX_LEADING_LETTER_PENALTY (-15)
 // penalty for every letter that doesn't match
-#define UNMATCHED_LETTER_PENALTY -1
+#define UNMATCHED_LETTER_PENALTY (-1)
 // penalty for gap in matching positions (-2 * k)
-#define GAP_PENALTY	-2
+#define GAP_PENALTY	(-2)
 // Score for a string that doesn't fuzzy match the pattern
-#define SCORE_NONE	-9999
+#define SCORE_NONE	(-9999)
 
 #define FUZZY_MATCH_RECURSION_LIMIT	10