Formatting: normalise back to 4-space indentation.

In several pieces of development recently I've run across the
occasional code block in the middle of a function which suddenly
switched to 2-space indent from this code base's usual 4. I decided I
was tired of it, so I ran the whole code base through a re-indenter,
which made a huge mess, and then manually sifted out the changes that
actually made sense from that pass.

Indeed, this caught quite a few large sections with 2-space indent
level, a couple with 8, and a handful of even weirder things like 3
spaces or 12. This commit fixes them all.

charset/localenc.c

@@ -103,7 +103,7 @@ int charset_from_localenc(const char *name)
         p = name;
         q = localencs[i].name;
         while (*p || *q) {
-                if (tolower((unsigned char)*p) != tolower((unsigned char)*q))
+            if (tolower((unsigned char)*p) != tolower((unsigned char)*q))
                 break;
             p++; q++;
         }

charset/mimeenc.c

@@ -207,7 +207,7 @@ int charset_from_mimeenc(const char *name)
         p = name;
         q = mimeencs[i].name;
         while (*p || *q) {
-                if (tolower((unsigned char)*p) != tolower((unsigned char)*q))
+            if (tolower((unsigned char)*p) != tolower((unsigned char)*q))
                 break;
             p++; q++;
         }

charset/xenc.c

@@ -82,7 +82,7 @@ int charset_from_xenc(const char *name)
         p = name;
         q = xencs[i].name;
         while (*p || *q) {
-                if (tolower((unsigned char)*p) != tolower((unsigned char)*q))
+            if (tolower((unsigned char)*p) != tolower((unsigned char)*q))
                 break;
             p++; q++;
         }