Fix meridian type in getdate.y

Commit d3356bc (ticket 8927)
incorrectly tagged tMERIDIAN as <Number>.  So while the lexer assigns
meridian values to the Meridian union field, the parser erroneously
reads them from the Number field.  On 64-bit IBM zSystems (s390x),
this can result in using the most recently read number as a meridian
value, leading to an abort in ToSeconds().

Fix the tMERIDIAN token type to be <Meridian>.

[ghudson@mit.edu: edited commit message]

(cherry picked from commit 0108d7d)

ticket: 9087
version_fixed: 1.20.2

src/kadmin/cli/getdate.y

@@ -181,7 +181,8 @@ static time_t	yyRelSeconds;
 
 %token			tAGO tID tDST tNEVER
 %token	<Number>	tDAY tDAYZONE tMINUTE_UNIT tMONTH tMONTH_UNIT
-%token	<Number>	tSEC_UNIT tSNUMBER tUNUMBER tZONE tMERIDIAN
+%token	<Number>	tSEC_UNIT tSNUMBER tUNUMBER tZONE
+%token	<Meridian>	tMERIDIAN
 %type	<Meridian>	o_merid
 
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