Editorial: avoid reusing/overwriting metavariable _p_

... in UnicodeMatchProperty.

spec.html

@@ -30383,8 +30383,8 @@ <h1>Runtime Semantics: UnicodeMatchProperty ( _p_ )</h1>
           <p>The abstract operation UnicodeMatchProperty takes a parameter _p_ that is a List of Unicode code points and performs the following steps:</p>
           <emu-alg>
             1. Assert: _p_ is a List of Unicode code points that is identical to a List of Unicode code points that is a Unicode property name or property alias listed in the &ldquo;Property name and aliases&rdquo; column of <emu-xref href="#table-nonbinary-unicode-properties"></emu-xref> or <emu-xref href="#table-binary-unicode-properties"></emu-xref>.
-            1. Let _p_ be the canonical property name of _p_ as given in the &ldquo;Canonical property name&rdquo; column of the corresponding row.
-            1. Return the List of Unicode code points of _p_.
+            1. Let _c_ be the canonical property name of _p_ as given in the &ldquo;Canonical property name&rdquo; column of the corresponding row.
+            1. Return the List of Unicode code points of _c_.
           </emu-alg>
           <p>Implementations must support the Unicode property names and aliases listed in <emu-xref href="#table-nonbinary-unicode-properties"></emu-xref> and <emu-xref href="#table-binary-unicode-properties"></emu-xref>. To ensure interoperability, implementations must not support any other property names or aliases.</p>
           <emu-note>