[install-guide] actually follow the suggestion from bz1175759 because it's a good idea

[Pete Travis]

commit 0e3ac6705f290024ab76c0e48cd14141c5ccd351
Author: Pete Travis <immanetize at fedoraproject.org>
Date:   Wed Dec 24 13:34:05 2014 -0700

    actually follow the suggestion from bz1175759 because it's a good idea

 en-US/Preparing_for_Installation.xml |    6 +++---
 1 files changed, 3 insertions(+), 3 deletions(-)
---
diff --git a/en-US/Preparing_for_Installation.xml b/en-US/Preparing_for_Installation.xml
index 0c3325b..b3430e9 100644
--- a/en-US/Preparing_for_Installation.xml
+++ b/en-US/Preparing_for_Installation.xml
@@ -99,7 +99,7 @@ Mode                LastWriteTime         Length  Name
 <command><prompt>&gt;</prompt> $image = "Fedora-Server-DVD-x86_64-21.iso"</command>
 <command><prompt>&gt;</prompt> $checksum_file = "Fedora-Server-21-x86_64-CHECKSUM"</command>
 <command><prompt>&gt;</prompt> $sha256 = New-Object -TypeName System.Security.Cryptography.sha256CryptoServiceProvider</command>
-<command><prompt>&gt;</prompt> $expected_checksum = ((Get-Content $checksum_file | Select-String -Pattern $image) -split " ")[0]</command>
+<command><prompt>&gt;</prompt> $expected_checksum = ((Get-Content $checksum_file | Select-String -Pattern $image) -split " ")[0].ToLower()</command>
             </screen>
           </step>
           <step>
@@ -107,7 +107,7 @@ Mode                LastWriteTime         Length  Name
               Calculate the downloaded image's checksum. This will take a while!
             </para>
             <screen>
-<command><prompt>&gt;</prompt> $download_checksum = [System.BitConverter]::ToString($sha256.ComputeHash([System.IO.File]::ReadAllBytes("$PWD\$image")))</command>
+<command><prompt>&gt;</prompt> $download_checksum = [System.BitConverter]::ToString($sha256.ComputeHash([System.IO.File]::ReadAllBytes("$PWD\$image"))).ToLower() -replace '-', ''</command>
              </screen>
             </step>
             <step>
@@ -117,7 +117,7 @@ Mode                LastWriteTime         Length  Name
               <programlisting>
 <prompt>&gt;</prompt> echo "Download Checksum: $download_checksum"
 <prompt>&gt;</prompt> echo "Expected Checksum: $expected_checksum"
-<prompt>&gt;</prompt> if ( $download_checksum -replace '-', '' -eq "$expected_checksum" ) {
+<prompt>&gt;</prompt> if ( $download_checksum -eq "$expected_checksum" ) {
     echo "Checksum test passed!"
 } else {
     echo "Checksum test failed."