qapi: Smooth another visitor error checking pattern

Convert

    visit_type_FOO(v, ..., &ptr, &err);
    ...
    if (err) {
        ...
    }

to

    visit_type_FOO(v, ..., &ptr, errp);
    ...
    if (!ptr) {
        ...
    }

for functions that set @ptr to non-null / null on success / error.

Eliminate error_propagate() that are now unnecessary.  Delete @err
that are now unused.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20200707160613.848843-40-armbru@redhat.com>

1 files changed, 2 insertions, 3 deletions

diff --git a/hw/acpi/core.c b/hw/acpi/core.c
index 8b240c3e09..f6d9ec4f13 100644
--- a/hw/acpi/core.c
+++ b/hw/acpi/core.c
@@ -239,7 +239,6 @@ static void acpi_table_install(const char unsigned *blob, size_t bloblen,
 void acpi_table_add(const QemuOpts *opts, Error **errp)
 {
     AcpiTableOptions *hdrs = NULL;
-    Error *err = NULL;
     char **pathnames = NULL;
     char **cur;
     size_t bloblen = 0;
@@ -249,11 +248,11 @@ void acpi_table_add(const QemuOpts *opts, Error **errp)
         Visitor *v;
 
         v = opts_visitor_new(opts);
-        visit_type_AcpiTableOptions(v, NULL, &hdrs, &err);
+        visit_type_AcpiTableOptions(v, NULL, &hdrs, errp);
         visit_free(v);
     }
 
-    if (err) {
+    if (!hdrs) {
         goto out;
     }
     if (hdrs->has_file == hdrs->has_data) {