Fix typos in comments.

Mostly misspellings of "function".

src/backend/cdb/cdbgroup.c

@@ -4363,7 +4363,7 @@ finalize_split_expr_mutator(Node *node, MppGroupContext *ctx)
 
 /* Function lookup_agg_transtype
  *
- * Return the transition type Oid of the given aggregate fuction or throw
+ * Return the transition type Oid of the given aggregate function or throw
  * an error, if none.
  */
 static Oid

src/include/access/formatter.h

@@ -50,7 +50,7 @@ typedef struct FormatterData
 	/* formatting */
 	StringInfoData	fmt_databuf;
 	bool			fmt_saw_eof;
-	FmgrInfo   	   *fmt_conv_funcs; /* in_fuctions (RET) or out_functions (WET) */
+	FmgrInfo   	   *fmt_conv_funcs; /* in_functions (RET) or out_functions (WET) */
 	Oid            *fmt_typioparams;
 	MemoryContext	fmt_perrow_ctx;
 	void		   *fmt_user_ctx;

src/include/gpopt/translate/CTranslatorQueryToDXL.h

@@ -209,7 +209,7 @@ namespace gpdxl
 			// update window spec positions of LEAD/LAG functions
 			void UpdateLeadLagWinSpecPos(CDXLNode *project_list_dxlnode, CDXLWindowSpecArray *window_specs_dxlnode) const;
 
-			// manufucture window frame for lead/lag functions
+			// manufacture window frame for lead/lag functions
 			CDXLWindowFrame *CreateWindowFramForLeadLag(BOOL is_lead_func, CDXLNode *dxl_offset) const;
 
 			// translate the child of a set operation