Pre-beta mechanical code beautification.

Run pgindent, pgperltidy, and reformat-dat-files.

This set of diffs is a bit larger than typical.  We've updated to
pg_bsd_indent 2.1.2, which properly indents variable declarations that
have multi-line initialization expressions (the continuation lines are
now indented one tab stop).  We've also updated to perltidy version
20230309 and changed some of its settings, which reduces its desire to
add whitespace to lines to make assignments etc. line up.  Going
forward, that should make for fewer random-seeming changes to existing
code.

Discussion: https://postgr.es/m/20230428092545.qfb3y5wcu4cm75ur@alvherre.pgsql

src/include/access/amapi.h

@@ -245,7 +245,7 @@ typedef struct IndexAmRoutine
 	/* does AM use maintenance_work_mem? */
 	bool		amusemaintenanceworkmem;
 	/* does AM store tuple information only at block granularity? */
-	bool        amsummarizing;
+	bool		amsummarizing;
 	/* OR of parallel vacuum flags.  See vacuum.h for flags. */
 	uint8		amparallelvacuumoptions;
 	/* type of data stored in index, or InvalidOid if variable */

src/include/access/brin_tuple.h

@@ -44,7 +44,7 @@ typedef struct BrinValues
 typedef struct BrinMemTuple
 {
 	bool		bt_placeholder; /* this is a placeholder tuple */
-	bool		bt_empty_range;	/* range represents no tuples */
+	bool		bt_empty_range; /* range represents no tuples */
 	BlockNumber bt_blkno;		/* heap blkno that the tuple is for */
 	MemoryContext bt_context;	/* memcxt holding the bt_columns values */
 	/* output arrays for brin_deform_tuple: */

src/include/access/gist_private.h

@@ -550,6 +550,7 @@ extern void gistSplitByKey(Relation r, Page page, IndexTuple *itup,
 /* gistbuild.c */
 extern IndexBuildResult *gistbuild(Relation heap, Relation index,
 								   struct IndexInfo *indexInfo);
+
 /* gistbuildbuffers.c */
 extern GISTBuildBuffers *gistInitBuildBuffers(int pagesPerBuffer, int levelStep,
 											  int maxLevel);

src/include/access/tableam.h

@@ -902,7 +902,7 @@ table_beginscan(Relation rel, Snapshot snapshot,
 				int nkeys, struct ScanKeyData *key)
 {
 	uint32		flags = SO_TYPE_SEQSCAN |
-	SO_ALLOW_STRAT | SO_ALLOW_SYNC | SO_ALLOW_PAGEMODE;
+		SO_ALLOW_STRAT | SO_ALLOW_SYNC | SO_ALLOW_PAGEMODE;
 
 	return rel->rd_tableam->scan_begin(rel, snapshot, nkeys, key, NULL, flags);
 }

src/include/access/xlogreader.h

@@ -332,6 +332,7 @@ extern XLogReaderState *XLogReaderAllocate(int wal_segment_size,
 										   const char *waldir,
 										   XLogReaderRoutine *routine,
 										   void *private_data);
+
 /* Free an XLogReader */
 extern void XLogReaderFree(XLogReaderState *state);