glibc: Remove sed and option unneeded with 2.38

--disable-crypt is now the default, and the security fix for 2.37 is
included.

chapter05/glibc.xml

@@ -91,7 +91,6 @@ cd       build</userinput></screen>
       --build=$(../scripts/config.guess) \
       --enable-kernel=&min-kernel;               \
       --with-headers=$LFS/usr/include    \
-      --disable-crypt                    \
       libc_cv_slibdir=/usr/lib</userinput></screen>
 
     <variablelist>

chapter08/glibc.xml

@@ -50,16 +50,6 @@
 
 <screen><userinput remap="pre">patch -Np1 -i ../&glibc-fhs-patch;</userinput></screen>
 
-    <!-- https://sourceware.org/bugzilla/show_bug.cgi?id=30068
-         Upstream fix also added a test case and renamed "prec" to
-         "prec_inc".  We'll test this with MPFR test suite so we don't
-         need the test here, and the renaming does not affect program
-         behavior.  -->
-    <para>Fix a security issue identified upstream:</para>
-
-<screen><userinput remap="pre">sed '/width -=/s/workend - string/number_length/' \
-    -i stdio-common/vfprintf-process-arg.c</userinput></screen>
-
     <para>The Glibc documentation recommends building Glibc
     in a dedicated build directory:</para>
 
@@ -79,7 +69,6 @@ cd       build</userinput></screen>
              --enable-kernel=&min-kernel;                     \
              --enable-stack-protector=strong          \
              --with-headers=/usr/include              \
-             --disable-crypt                          \
              libc_cv_slibdir=/usr/lib</userinput></screen>
 
     <variablelist>