Merge pull request #24799 from poettering/initrd-ftw

use "initrd" rather than "initial RAM disk" or "initramfs" to refernce the concept

test/README.testsuite

@@ -98,8 +98,8 @@ INTERACTIVE_DEBUG=1
     (e.g. by setting a usable default terminal, suppressing the shutdown after
     the test, etc.)
 
-The kernel and initramfs can be specified with $KERNEL_BIN and $INITRD.
-(Fedora's or Debian's default kernel path and initramfs are used by default)
+The kernel and initrd can be specified with $KERNEL_BIN and $INITRD. (Fedora's
+or Debian's default kernel path and initrd are used by default)
 
 A script will try to find your qemu binary. If you want to specify a different
 one with $QEMU_BIN.

test/test-functions

@@ -2716,7 +2716,7 @@ inst() {
 # inst_any -d /bin/foo /bin/bar /bin/baz
 #
 # Lets assume that /bin/baz exists, so it will be installed as /bin/foo in
-# initramfs.
+# initrd.
 inst_any() {
     local dest file