USHRT_MAX -> SAL_MAX_UINT16

...presumably forgotten when the following casts of nTmp in the SetBaseHeight
etc. calls were changed from USHORT to sal_uInt16 in
7f33ed41 "removetooltypes01: #i112600# Remove
tools types from sw"

Change-Id: I75809e677835910b09b366f755361a667d097402
Reviewed-on: https://gerrit.libreoffice.org/48442Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>

sw/source/core/layout/atrfrm.cxx

@@ -2322,7 +2322,7 @@ bool SwTextGridItem::PutValue( const uno::Any& rVal, sal_uInt8 nMemberId )
             sal_Int32 nTmp = 0;
             bRet = (rVal >>= nTmp);
             nTmp = convertMm100ToTwip( nTmp );
-            if( bRet && (nTmp >= 0) && ( nTmp <= USHRT_MAX) )
+            if( bRet && (nTmp >= 0) && ( nTmp <= SAL_MAX_UINT16) )
             {
                 // rhbz#1043551 round up to 5pt -- 0 causes divide-by-zero
                 // in layout; 1pt ties the painting code up in knots for