Tweak linux_glibc properties for musl builds in build/soong

For convenience, builds against musl libc currently use the
linux_glibc properties because they are almost always linux-specific
and not glibc-specific.  In preparation for removing this hack,
tweak the linux_glibc properties by either moving them to host_linux,
which will apply to linux_glibc, linux_musl and linux_bionic, or
by setting appropriate musl or linux_musl properties.  Properties
that must not be repeated while musl uses linux_musl and also still
uses the linux_glibc properties are moved to glibc properties, which
don't apply to musl.  Whether these stay as glibc properties or get
moved back to linux_glibc later once the musl hack is removed is TBD.

Bug: 223257095
Test: m checkbuild
Test: m USE_HOST_MUSL=true host-native
Change-Id: I04833c36fe267d218257c8910056ed4106ca8f3b

Android.bp

@@ -61,6 +61,9 @@ cc_genrule {
         linux_bionic: {
             enabled: true,
         },
+        linux_musl: {
+            enabled: false,
+        },
         linux_glibc: {
             enabled: false,
         },
@@ -82,6 +85,9 @@ cc_genrule {
         linux_bionic: {
             enabled: true,
         },
+        linux_musl: {
+            enabled: false,
+        },
         linux_glibc: {
             enabled: false,
         },