docs: Update the AMD SEV's spec URL

Luckily, the new URL still points to the same location, the only change
is in the document name where an escaped space (%20) was replaced by an
underscore.
Signed-off-by: NErik Skultety <eskultet@redhat.com>
Reviewed-by: NAndrea Bolognani <abologna@redhat.com>

docs/formatdomain.html.in

@@ -8785,8 +8785,8 @@ qemu-kvm -net nic,model=? /dev/null
        different entity using a different key the encrypted guests data will
        be incorrectly decrypted, leading to unintelligible data.
 
-       For more information see various input parameters and its format see the SEV API spec
-       <a href="https://support.amd.com/TechDocs/55766_SEV-KM%20API_Specification.pdf"> https://support.amd.com/TechDocs/55766_SEV-KM%20API_Specification.pdf </a>
+       For more information see various input parameters and its format see the
+       <a href="https://support.amd.com/TechDocs/55766_SEV-KM_API_Specification.pdf">SEV API spec</a>
        <span class="since">Since 4.4.0</span>
        </p>
     <pre>

docs/formatdomaincaps.html.in

@@ -481,7 +481,7 @@
 
     <p>
     For more details on SEV feature see:
-      <a href="https://support.amd.com/TechDocs/55766_SEV-KM%20API_Specification.pdf">
+      <a href="https://support.amd.com/TechDocs/55766_SEV-KM_API_Specification.pdf">
         SEV API spec</a> and <a href="http://amd-dev.wpengine.netdna-cdn.com/wordpress/media/2013/12/AMD_Memory_Encryption_Whitepaper_v7-Public.pdf">
         SEV White Paper</a>
     </p>