Rename target.linux[_x86[_64]] to target.linux_glibc[_x86[_64]]

In the future, target.linux will apply to all targets running a linux kernel
(android, linux_glibc, linux_bionic). So move all current users to the specific
linux_glibc.

There will be another cleanup pass later that will move some instances back to
target.linux if the properties should be shared with target.android and
target.linux_bionic, but target.linux needs to be removed first.

Test: out/soong/build.ninja identical before/after
Change-Id: I72ef34689c60ce547cab2898e354b027e335f6a1
Exempt-From-Owner-Approval: build system cleanup

base/Android.bp

@@ -89,7 +89,7 @@ cc_library {
             cppflags: ["-Wexit-time-destructors"],
             enabled: true,
         },
-        linux: {
+        linux_glibc: {
             srcs: [
                 "chrono_utils.cpp",
                 "errors_unix.cpp",
@@ -135,7 +135,7 @@ cc_test {
                 misc_undefined: ["integer"],
             },
         },
-        linux: {
+        linux_glibc: {
             srcs: ["chrono_utils_test.cpp"],
         },
         windows: {

libbacktrace/Android.bp

@@ -83,7 +83,7 @@ cc_library {
         darwin: {
             enabled: true,
         },
-        linux: {
+        linux_glibc: {
             srcs: libbacktrace_sources,
 
             shared_libs: [
@@ -135,7 +135,7 @@ cc_library_shared {
     srcs: ["backtrace_testlib.cpp"],
 
     target: {
-        linux: {
+        linux_glibc: {
             shared_libs: [
                 "libunwind",
                 "libunwindstack",
@@ -231,7 +231,7 @@ cc_test {
                 "libutils",
             ],
         },
-        linux: {
+        linux_glibc: {
             host_ldlibs: [
                 "-lncurses",
             ],

libdiskconfig/Android.bp

@@ -23,7 +23,7 @@ cc_library {
         darwin: {
             enabled: false,
         },
-        linux: {
+        linux_glibc: {
             cflags: [
                 "-O2",
                 "-g",

libutils/Android.bp

@@ -121,7 +121,7 @@ cc_library {
             },
         },
 
-        linux: {
+        linux_glibc: {
             srcs: [
                 "Looper.cpp",
                 "ProcessCallStack.cpp",

libutils/tests/Android.bp

@@ -46,7 +46,7 @@ cc_test {
                 "libbase",
             ],
         },
-        linux: {
+        linux_glibc: {
             srcs: [
                 "Looper_test.cpp",
                 "RefBase_test.cpp",