Replace (e)glibc by glibc

Following the removal of eglibc support, this commit replaces all
occurences of "(e)glibc" by just "glibc". Most of the occurences are in
package Config.in comments.

In addition, when the form "an (e)glibc ..." was used, it is replaced by
"a glibc ...".

[Peter: add new efi* packages, s/uclibc/uClibc as suggested by Romain,
        systemd / liquid-dsp tweaks as suggested by Yann]
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Reviewed-by: Romain Naour <romain.naour@gmail.com>
Acked-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

docs/manual/adding-packages-directory.txt

@@ -311,7 +311,7 @@ use in the comment.
 ** Dependency symbol: +BR2_TOOLCHAIN_USES_GLIBC+,
    +BR2_TOOLCHAIN_USES_MUSL+, +BR2_TOOLCHAIN_USES_UCLIBC+
 ** Comment string: for the C library, a slightly different comment text
-   is used: +foo needs an (e)glibc toolchain+, or `foo needs an (e)glibc
+   is used: +foo needs a glibc toolchain+, or `foo needs a glibc
    toolchain w/ C++`
 
 * C++ support