[LyX/master] Does not compile on older gcc.

[Pavel Sanda]

commit bd5f6097fc33d24f39660c38267793f6776f6cd7
Author: Pavel Sanda <sanda at lyx.org>
Date:   Tue Aug 4 14:54:15 2020 +0200

    Does not compile on older gcc.
---
 src/insets/InsetBibtex.cpp |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/insets/InsetBibtex.cpp b/src/insets/InsetBibtex.cpp
index 95c93a1..876adea 100644
--- a/src/insets/InsetBibtex.cpp
+++ b/src/insets/InsetBibtex.cpp
@@ -1183,8 +1183,8 @@ void InsetBibtex::docbook(XMLStream & xs, OutputParams const &) const
 		string html = to_utf8(bibinfo.getInfo(entry.key(), buffer(), ci));
 		regex tagRegex("<span class=\"bib-([^\"]*)\">([^<]*)</span>");
 		smatch match;
-		auto tagIt = std::sregex_iterator(html.cbegin(), html.cend(), tagRegex, regex_constants::match_default);
-		auto tagEnd = std::sregex_iterator();
+		auto tagIt = lyx::sregex_iterator(html.cbegin(), html.cend(), tagRegex, regex_constants::match_default);
+		auto tagEnd = lyx::sregex_iterator();
 		map<string, string> delayedTags;
 
 		// Read all tags from HTML and convert those that have a 1:1 matching.