fixes #22676; remove wMerge which is a noop for more than 8 years (#22678)

fixes #22676

If csource or CI forbids it, we can always fall back to adding it to the
nonPragmaWords list. I doubt it was used outside of the system since it
was used to implement & or something for magics.

compiler/pragmas.nim

@@ -29,7 +29,7 @@ const
     ## common pragmas for declarations, to a good approximation
   procPragmas* = declPragmas + {FirstCallConv..LastCallConv,
     wMagic, wNoSideEffect, wSideEffect, wNoreturn, wNosinks, wDynlib, wHeader,
-    wCompilerProc, wNonReloadable, wCore, wProcVar, wVarargs, wCompileTime, wMerge,
+    wCompilerProc, wNonReloadable, wCore, wProcVar, wVarargs, wCompileTime,
     wBorrow, wImportCompilerProc, wThread,
     wAsmNoStackFrame, wDiscardable, wNoInit, wCodegenDecl,
     wGensym, wInject, wRaises, wEffectsOf, wTags, wForbids, wLocks, wDelegator, wGcSafe,
@@ -971,9 +971,6 @@ proc singlePragma(c: PContext, sym: PSym, n: PNode, i: var int,
         noVal(c, it)
         incl(sym.flags, sfGlobal)
         incl(sym.flags, sfPure)
-      of wMerge:
-        # only supported for backwards compat, doesn't do anything anymore
-        noVal(c, it)
       of wConstructor:
         incl(sym.flags, sfConstructor)
         if sfImportc notin sym.flags:

compiler/wordrecg.nim

@@ -49,7 +49,7 @@ type
     wCompleteStruct = "completeStruct", wRequiresInit = "requiresInit", wAlign = "align",
     wNodecl = "nodecl", wPure = "pure", wSideEffect = "sideEffect", wHeader = "header",
     wNoSideEffect = "noSideEffect", wGcSafe = "gcsafe", wNoreturn = "noreturn",
-    wNosinks = "nosinks", wMerge = "merge", wLib = "lib", wDynlib = "dynlib",
+    wNosinks = "nosinks", wLib = "lib", wDynlib = "dynlib",
     wCompilerProc = "compilerproc", wCore = "core", wProcVar = "procvar",
     wBase = "base", wUsed = "used", wFatal = "fatal", wError = "error", wWarning = "warning",
     wHint = "hint",