libdwfl: switch to DEBUGINFOD_SONAME, remove libdebuginfod.so fallback

Since DEBUGINFOD_SONAME is as good as ("libdebuginfod-" VERSION ".so")
for dlopen, switch to use the name which is a part of the API.

Given that DEBUGINFOD_SONAME is always available now, remove the no longer
needed fall back to dlopen of "libdebuginfod.so".

Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
diff --git a/libdwfl/ChangeLog b/libdwfl/ChangeLog
index f11abb8..444e093 100644
--- a/libdwfl/ChangeLog
+++ b/libdwfl/ChangeLog
@@ -1,3 +1,9 @@
+2020-12-08  Dmitry V. Levin  <ldv@altlinux.org>
+
+	* debuginfod-client.c (__libdwfl_debuginfod_init): Replace
+	"libdebuginfod-" VERSION ".so" with DEBUGINFOD_SONAME in dlopen call.
+	Do not fall back to dlopen of "libdebuginfod.so".
+
 2020-12-01  Timm Bäder  <tbaeder@redhat.com>
 
 	* link_map.c (dwfl_link_map_report): Removed consider_phdr function
diff --git a/libdwfl/debuginfod-client.c b/libdwfl/debuginfod-client.c
index ee604ad..99b66b6 100644
--- a/libdwfl/debuginfod-client.c
+++ b/libdwfl/debuginfod-client.c
@@ -101,10 +101,7 @@
 void __attribute__ ((constructor))
 __libdwfl_debuginfod_init (void)
 {
-  void *debuginfod_so = dlopen("libdebuginfod-" VERSION ".so", RTLD_LAZY);
-
-  if (debuginfod_so == NULL)
-    debuginfod_so = dlopen("libdebuginfod.so", RTLD_LAZY);
+  void *debuginfod_so = dlopen(DEBUGINFOD_SONAME, RTLD_LAZY);
 
   if (debuginfod_so != NULL)
     {