libgcc: Synchronise stub port version with GCC version

lang/libgcc/Portfile

@@ -3,9 +3,14 @@
 PortSystem          1.0
 PortGroup select    1.0
 
-epoch               3
+# Pick the gcc version that provides the primary runtime.
+# NOTE : The logic here must match that in the gccX ports *and*
+# that in _resources/port1.0/group/compilers-1.0.tcl
+set gcc_version     15
+
 name                libgcc
-version             10.0
+epoch               3
+version             ${gcc_version}
 revision            0
 
 conflicts           libgcc-devel
@@ -17,9 +22,8 @@ distfiles
 
 use_configure       no
 
-description         Provides the appropriate gcc runtime.
-long_description    {*}${description} \
-                    Picks the version to use based on macOS version.
+description         Provides the gcc runtime based on major version ${gcc_version}
+long_description    {*}${description}
 
 license             BSD
 platforms           any
@@ -28,12 +32,7 @@ homepage            https://www.macports.org/
 
 variant universal   { }
 
-# Pick the gcc version that provides the primary runtime.
-# NOTE : The logic here must match that in the gccX ports *and*
-# that in _resources/port1.0/group/compilers-1.0.tcl
-set gcc_version 15
-
-depends_lib port:libgcc${gcc_version}
+depends_lib         port:libgcc${gcc_version}
 
 build { }
 
@@ -41,10 +40,3 @@ destroot {
    xinstall -d ${destroot}${prefix}/share/doc/${name}
    system "echo 'libgcc runtime is provided by libgcc${gcc_version}' > ${destroot}${prefix}/share/doc/${name}/README"
 }
-
-#post-deactivate {
-#    # When this port is deactivated, the associated libgccX should also be.
-#    if {![catch {set installed [lindex [registry_active libgcc${gcc_version}] 0]}]} {
-#        registry_deactivate_composite libgcc${gcc_version} "" [list ports_nodepcheck 1]
-#    }
-#}