Support IPMI Serial Transport

Support IPMI Serial interface (basic mode) based on Sec 14,
IPMI 2.0 spec. Serial transport tested with meta-evb-arm
platform with socat and ipmitool.

HW transport can be selected by meson configure flasg.

Tested:

1. socat -x pty,raw,echo=0,link=/tmp/ttyHOST2BMC tcp:localhost:5066
2. ipmitool -I serial-basic -D /tmp/ttyHOST2BMC:115200 mc info

    Device ID                 : 0
    Device Revision           : 0
    Firmware Revision         : 2.17
    IPMI Version              : 2.0
    Manufacturer ID           : 0
    Manufacturer Name         : Unknown
    Product ID                : 0 (0x0000)
    Product Name              : Unknown (0x0)
    Device Available          : no
    Provides Device SDRs      : no
    Additional Device Support :
    Aux Firmware Rev Info     :
        0x00
        0x00
        0x00
        0x00

Change-Id: I2a56390022fce7a974ed75ed6a72ad3fffed9bb6
Signed-off-by: John Chung <john.chung@arm.com>
diff --git a/transport/serialbridge/meson.build b/transport/serialbridge/meson.build
new file mode 100644
index 0000000..2964206
--- /dev/null
+++ b/transport/serialbridge/meson.build
@@ -0,0 +1,38 @@
+CLI11_dep = dependency('CLI11')
+
+deps = [
+    dependency('libsystemd'),
+    dependency('systemd'),
+    sdeventplus_dep,
+    stdplus_dep,
+    sdbusplus_dep,
+    phosphor_logging_dep,
+    CLI11_dep
+]
+
+serialbridged = executable(
+    'serialbridged',
+    'serialbridged.cpp',
+    'serialcmd.cpp',
+    dependencies: deps,
+    install: true,
+    install_dir: get_option('libexecdir')
+)
+
+# Configure and install systemd unit files
+systemd = dependency('systemd')
+if systemd.found()
+    conf_data = configuration_data()
+    conf_data.set('BIN', get_option('prefix') / get_option('libexecdir') / serialbridged.name())
+    configure_file(
+        input: 'serialbridge@.service.in',
+        output: 'serialbridge@.service',
+        configuration: conf_data,
+        install: true,
+        install_dir: systemd.get_variable(pkgconfig: 'systemdsystemunitdir')
+    )
+endif
+
+if not get_option('tests').disabled()
+    subdir('test')
+endif